Replace per-target ABI denylist with an allowlist

It makes very little sense to maintain denylists of ABIs when, as far as
non-generic ABIs are concerned, targets usually only support a small
subset of the available ABIs.

This has historically been a cause of bugs such as us allowing use of
the platform-specific ABIs on x86 targets – these in turn would cause
LLVM errors or assertions to fire.

Fixes #57182

Sponsored by: standard.ai

66 files changed, 202 insertions, 427 deletions

diff --git a/compiler/rustc_target/src/spec/aarch64_apple_ios.rs b/compiler/rustc_target/src/spec/aarch64_apple_ios.rs
index 9fa8ef69d81..e5805d9e691 100644
--- a/compiler/rustc_target/src/spec/aarch64_apple_ios.rs
+++ b/compiler/rustc_target/src/spec/aarch64_apple_ios.rs
@@ -2,7 +2,6 @@ use super::apple_sdk_base::{opts, Arch};
 use crate::spec::{FramePointer, Target, TargetOptions};
 
 pub fn target() -> Target {
-    let base = opts("ios", Arch::Arm64);
     Target {
         llvm_target: "arm64-apple-ios".to_string(),
         pointer_width: 64,
@@ -11,7 +10,6 @@ pub fn target() -> Target {
         options: TargetOptions {
             features: "+neon,+fp-armv8,+apple-a7".to_string(),
             max_atomic_width: Some(128),
-            unsupported_abis: super::arm_base::unsupported_abis(),
             forces_embed_bitcode: true,
             frame_pointer: FramePointer::NonLeaf,
             // Taken from a clang build on Xcode 11.4.1.
@@ -25,7 +23,7 @@ pub fn target() -> Target {
                 darwinpcs\0\
                 -Os\0"
                 .to_string(),
-            ..base
+            ..opts("ios", Arch::Arm64)
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/aarch64_apple_ios_macabi.rs b/compiler/rustc_target/src/spec/aarch64_apple_ios_macabi.rs
index a43eb99a1d7..d16328f00f9 100644
--- a/compiler/rustc_target/src/spec/aarch64_apple_ios_macabi.rs
+++ b/compiler/rustc_target/src/spec/aarch64_apple_ios_macabi.rs
@@ -2,7 +2,6 @@ use super::apple_sdk_base::{opts, Arch};
 use crate::spec::{FramePointer, Target, TargetOptions};
 
 pub fn target() -> Target {
-    let base = opts("ios", Arch::Arm64_macabi);
     Target {
         llvm_target: "arm64-apple-ios14.0-macabi".to_string(),
         pointer_width: 64,
@@ -11,7 +10,6 @@ pub fn target() -> Target {
         options: TargetOptions {
             features: "+neon,+fp-armv8,+apple-a12".to_string(),
             max_atomic_width: Some(128),
-            unsupported_abis: super::arm_base::unsupported_abis(),
             forces_embed_bitcode: true,
             frame_pointer: FramePointer::NonLeaf,
             // Taken from a clang build on Xcode 11.4.1.
@@ -23,7 +21,7 @@ pub fn target() -> Target {
                 -disable-llvm-passes\0\
                 -Os\0"
                 .to_string(),
-            ..base
+            ..opts("ios", Arch::Arm64_macabi)
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/aarch64_apple_ios_sim.rs b/compiler/rustc_target/src/spec/aarch64_apple_ios_sim.rs
index 586e4043d79..07b3453218f 100644
--- a/compiler/rustc_target/src/spec/aarch64_apple_ios_sim.rs
+++ b/compiler/rustc_target/src/spec/aarch64_apple_ios_sim.rs
@@ -19,7 +19,6 @@ pub fn target() -> Target {
         options: TargetOptions {
             features: "+neon,+fp-armv8,+apple-a7".to_string(),
             max_atomic_width: Some(128),
-            unsupported_abis: super::arm_base::unsupported_abis(),
             forces_embed_bitcode: true,
             frame_pointer: FramePointer::NonLeaf,
             // Taken from a clang build on Xcode 11.4.1.
diff --git a/compiler/rustc_target/src/spec/aarch64_apple_tvos.rs b/compiler/rustc_target/src/spec/aarch64_apple_tvos.rs
index 934f3370369..b4bd72a082b 100644
--- a/compiler/rustc_target/src/spec/aarch64_apple_tvos.rs
+++ b/compiler/rustc_target/src/spec/aarch64_apple_tvos.rs
@@ -2,7 +2,6 @@ use super::apple_sdk_base::{opts, Arch};
 use crate::spec::{FramePointer, Target, TargetOptions};
 
 pub fn target() -> Target {
-    let base = opts("tvos", Arch::Arm64);
     Target {
         llvm_target: "arm64-apple-tvos".to_string(),
         pointer_width: 64,
@@ -11,10 +10,9 @@ pub fn target() -> Target {
         options: TargetOptions {
             features: "+neon,+fp-armv8,+apple-a7".to_string(),
             max_atomic_width: Some(128),
-            unsupported_abis: super::arm_base::unsupported_abis(),
             forces_embed_bitcode: true,
             frame_pointer: FramePointer::NonLeaf,
-            ..base
+            ..opts("tvos", Arch::Arm64)
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/aarch64_be_unknown_linux_gnu.rs b/compiler/rustc_target/src/spec/aarch64_be_unknown_linux_gnu.rs
index 192c4661c7c..71ee6deb07f 100644
--- a/compiler/rustc_target/src/spec/aarch64_be_unknown_linux_gnu.rs
+++ b/compiler/rustc_target/src/spec/aarch64_be_unknown_linux_gnu.rs
@@ -2,19 +2,16 @@ use crate::abi::Endian;
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let mut base = super::linux_gnu_base::opts();
-    base.max_atomic_width = Some(128);
-
     Target {
         llvm_target: "aarch64_be-unknown-linux-gnu".to_string(),
         pointer_width: 64,
         data_layout: "E-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128".to_string(),
         arch: "aarch64".to_string(),
         options: TargetOptions {
-            unsupported_abis: super::arm_base::unsupported_abis(),
+            max_atomic_width: Some(128),
             mcount: "\u{1}_mcount".to_string(),
             endian: Endian::Big,
-            ..base
+            ..super::linux_gnu_base::opts()
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/aarch64_be_unknown_linux_gnu_ilp32.rs b/compiler/rustc_target/src/spec/aarch64_be_unknown_linux_gnu_ilp32.rs
index 5b9e9c9519c..c1adc963425 100644
--- a/compiler/rustc_target/src/spec/aarch64_be_unknown_linux_gnu_ilp32.rs
+++ b/compiler/rustc_target/src/spec/aarch64_be_unknown_linux_gnu_ilp32.rs
@@ -10,11 +10,6 @@ pub fn target() -> Target {
         pointer_width: 32,
         data_layout: "E-m:e-p:32:32-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128".to_string(),
         arch: "aarch64".to_string(),
-        options: TargetOptions {
-            unsupported_abis: super::arm_base::unsupported_abis(),
-            mcount: "\u{1}_mcount".to_string(),
-            endian: Endian::Big,
-            ..base
-        },
+        options: TargetOptions { mcount: "\u{1}_mcount".to_string(), endian: Endian::Big, ..base },
     }
 }
diff --git a/compiler/rustc_target/src/spec/aarch64_fuchsia.rs b/compiler/rustc_target/src/spec/aarch64_fuchsia.rs
index c9cb21f1eb1..56d71df6bda 100644
--- a/compiler/rustc_target/src/spec/aarch64_fuchsia.rs
+++ b/compiler/rustc_target/src/spec/aarch64_fuchsia.rs
@@ -1,15 +1,15 @@
 use crate::spec::{SanitizerSet, Target, TargetOptions};
 
 pub fn target() -> Target {
-    let mut base = super::fuchsia_base::opts();
-    base.max_atomic_width = Some(128);
-    base.supported_sanitizers = SanitizerSet::ADDRESS;
-
     Target {
         llvm_target: "aarch64-fuchsia".to_string(),
         pointer_width: 64,
         data_layout: "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128".to_string(),
         arch: "aarch64".to_string(),
-        options: TargetOptions { unsupported_abis: super::arm_base::unsupported_abis(), ..base },
+        options: TargetOptions {
+            max_atomic_width: Some(128),
+            supported_sanitizers: SanitizerSet::ADDRESS,
+            ..super::fuchsia_base::opts()
+        },
     }
 }
diff --git a/compiler/rustc_target/src/spec/aarch64_linux_android.rs b/compiler/rustc_target/src/spec/aarch64_linux_android.rs
index d00883ae71a..409cab72ec2 100644
--- a/compiler/rustc_target/src/spec/aarch64_linux_android.rs
+++ b/compiler/rustc_target/src/spec/aarch64_linux_android.rs
@@ -4,17 +4,18 @@ use crate::spec::{SanitizerSet, Target, TargetOptions};
 // for target ABI requirements.
 
 pub fn target() -> Target {
-    let mut base = super::android_base::opts();
-    base.max_atomic_width = Some(128);
-    // As documented in https://developer.android.com/ndk/guides/cpu-features.html
-    // the neon (ASIMD) and FP must exist on all android aarch64 targets.
-    base.features = "+neon,+fp-armv8".to_string();
-    base.supported_sanitizers = SanitizerSet::HWADDRESS;
     Target {
         llvm_target: "aarch64-linux-android".to_string(),
         pointer_width: 64,
         data_layout: "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128".to_string(),
         arch: "aarch64".to_string(),
-        options: TargetOptions { unsupported_abis: super::arm_base::unsupported_abis(), ..base },
+        options: TargetOptions {
+            max_atomic_width: Some(128),
+            // As documented in https://developer.android.com/ndk/guides/cpu-features.html
+            // the neon (ASIMD) and FP must exist on all android aarch64 targets.
+            features: "+neon,+fp-armv8".to_string(),
+            supported_sanitizers: SanitizerSet::HWADDRESS,
+            ..super::android_base::opts()
+        },
     }
 }
diff --git a/compiler/rustc_target/src/spec/aarch64_unknown_freebsd.rs b/compiler/rustc_target/src/spec/aarch64_unknown_freebsd.rs
index d48389d4a35..09ea7d33cfd 100644
--- a/compiler/rustc_target/src/spec/aarch64_unknown_freebsd.rs
+++ b/compiler/rustc_target/src/spec/aarch64_unknown_freebsd.rs
@@ -1,14 +1,11 @@
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let mut base = super::freebsd_base::opts();
-    base.max_atomic_width = Some(128);
-
     Target {
         llvm_target: "aarch64-unknown-freebsd".to_string(),
         pointer_width: 64,
         data_layout: "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128".to_string(),
         arch: "aarch64".to_string(),
-        options: TargetOptions { unsupported_abis: super::arm_base::unsupported_abis(), ..base },
+        options: TargetOptions { max_atomic_width: Some(128), ..super::freebsd_base::opts() },
     }
 }
diff --git a/compiler/rustc_target/src/spec/aarch64_unknown_linux_gnu.rs b/compiler/rustc_target/src/spec/aarch64_unknown_linux_gnu.rs
index a07cd7db889..3e92ecbae05 100644
--- a/compiler/rustc_target/src/spec/aarch64_unknown_linux_gnu.rs
+++ b/compiler/rustc_target/src/spec/aarch64_unknown_linux_gnu.rs
@@ -1,23 +1,20 @@
 use crate::spec::{SanitizerSet, Target, TargetOptions};
 
 pub fn target() -> Target {
-    let mut base = super::linux_gnu_base::opts();
-    base.max_atomic_width = Some(128);
-    base.supported_sanitizers = SanitizerSet::ADDRESS
-        | SanitizerSet::LEAK
-        | SanitizerSet::MEMORY
-        | SanitizerSet::THREAD
-        | SanitizerSet::HWADDRESS;
-
     Target {
         llvm_target: "aarch64-unknown-linux-gnu".to_string(),
         pointer_width: 64,
         data_layout: "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128".to_string(),
         arch: "aarch64".to_string(),
         options: TargetOptions {
-            unsupported_abis: super::arm_base::unsupported_abis(),
             mcount: "\u{1}_mcount".to_string(),
-            ..base
+            max_atomic_width: Some(128),
+            supported_sanitizers: SanitizerSet::ADDRESS
+                | SanitizerSet::LEAK
+                | SanitizerSet::MEMORY
+                | SanitizerSet::THREAD
+                | SanitizerSet::HWADDRESS,
+            ..super::linux_gnu_base::opts()
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/aarch64_unknown_linux_gnu_ilp32.rs b/compiler/rustc_target/src/spec/aarch64_unknown_linux_gnu_ilp32.rs
index f2d7576280f..e2618447f28 100644
--- a/compiler/rustc_target/src/spec/aarch64_unknown_linux_gnu_ilp32.rs
+++ b/compiler/rustc_target/src/spec/aarch64_unknown_linux_gnu_ilp32.rs
@@ -1,18 +1,15 @@
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let mut base = super::linux_gnu_base::opts();
-    base.max_atomic_width = Some(128);
-
     Target {
         llvm_target: "aarch64-unknown-linux-gnu_ilp32".to_string(),
         pointer_width: 32,
         data_layout: "e-m:e-p:32:32-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128".to_string(),
         arch: "aarch64".to_string(),
         options: TargetOptions {
-            unsupported_abis: super::arm_base::unsupported_abis(),
+            max_atomic_width: Some(128),
             mcount: "\u{1}_mcount".to_string(),
-            ..base
+            ..super::linux_gnu_base::opts()
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/aarch64_unknown_linux_musl.rs b/compiler/rustc_target/src/spec/aarch64_unknown_linux_musl.rs
index 7bbfc8ec0f7..6a16b4ce419 100644
--- a/compiler/rustc_target/src/spec/aarch64_unknown_linux_musl.rs
+++ b/compiler/rustc_target/src/spec/aarch64_unknown_linux_musl.rs
@@ -9,10 +9,6 @@ pub fn target() -> Target {
         pointer_width: 64,
         data_layout: "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128".to_string(),
         arch: "aarch64".to_string(),
-        options: TargetOptions {
-            unsupported_abis: super::arm_base::unsupported_abis(),
-            mcount: "\u{1}_mcount".to_string(),
-            ..base
-        },
+        options: TargetOptions { mcount: "\u{1}_mcount".to_string(), ..base },
     }
 }
diff --git a/compiler/rustc_target/src/spec/aarch64_unknown_netbsd.rs b/compiler/rustc_target/src/spec/aarch64_unknown_netbsd.rs
index 09efbdbb293..4042028e2dc 100644
--- a/compiler/rustc_target/src/spec/aarch64_unknown_netbsd.rs
+++ b/compiler/rustc_target/src/spec/aarch64_unknown_netbsd.rs
@@ -1,15 +1,15 @@
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let mut base = super::netbsd_base::opts();
-    base.max_atomic_width = Some(128);
-    base.unsupported_abis = super::arm_base::unsupported_abis();
-
     Target {
         llvm_target: "aarch64-unknown-netbsd".to_string(),
         pointer_width: 64,
         data_layout: "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128".to_string(),
         arch: "aarch64".to_string(),
-        options: TargetOptions { mcount: "__mcount".to_string(), ..base },
+        options: TargetOptions {
+            mcount: "__mcount".to_string(),
+            max_atomic_width: Some(128),
+            ..super::netbsd_base::opts()
+        },
     }
 }
diff --git a/compiler/rustc_target/src/spec/aarch64_unknown_none.rs b/compiler/rustc_target/src/spec/aarch64_unknown_none.rs
index de92b167f00..9d365279010 100644
--- a/compiler/rustc_target/src/spec/aarch64_unknown_none.rs
+++ b/compiler/rustc_target/src/spec/aarch64_unknown_none.rs
@@ -18,7 +18,6 @@ pub fn target() -> Target {
         disable_redzone: true,
         max_atomic_width: Some(128),
         panic_strategy: PanicStrategy::Abort,
-        unsupported_abis: super::arm_base::unsupported_abis(),
         ..Default::default()
     };
     Target {
diff --git a/compiler/rustc_target/src/spec/aarch64_unknown_none_softfloat.rs b/compiler/rustc_target/src/spec/aarch64_unknown_none_softfloat.rs
index 2566eeae14a..482db0c5342 100644
--- a/compiler/rustc_target/src/spec/aarch64_unknown_none_softfloat.rs
+++ b/compiler/rustc_target/src/spec/aarch64_unknown_none_softfloat.rs
@@ -18,7 +18,6 @@ pub fn target() -> Target {
         disable_redzone: true,
         max_atomic_width: Some(128),
         panic_strategy: PanicStrategy::Abort,
-        unsupported_abis: super::arm_base::unsupported_abis(),
         ..Default::default()
     };
     Target {
diff --git a/compiler/rustc_target/src/spec/aarch64_unknown_openbsd.rs b/compiler/rustc_target/src/spec/aarch64_unknown_openbsd.rs
index 83ba1ecd1d3..193f9814210 100644
--- a/compiler/rustc_target/src/spec/aarch64_unknown_openbsd.rs
+++ b/compiler/rustc_target/src/spec/aarch64_unknown_openbsd.rs
@@ -1,15 +1,11 @@
-use crate::spec::Target;
+use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let mut base = super::openbsd_base::opts();
-    base.max_atomic_width = Some(128);
-    base.unsupported_abis = super::arm_base::unsupported_abis();
-
     Target {
         llvm_target: "aarch64-unknown-openbsd".to_string(),
         pointer_width: 64,
         data_layout: "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128".to_string(),
         arch: "aarch64".to_string(),
-        options: base,
+        options: TargetOptions { max_atomic_width: Some(128), ..super::openbsd_base::opts() },
     }
 }
diff --git a/compiler/rustc_target/src/spec/aarch64_wrs_vxworks.rs b/compiler/rustc_target/src/spec/aarch64_wrs_vxworks.rs
index beb8ce30cc9..66140060f8e 100644
--- a/compiler/rustc_target/src/spec/aarch64_wrs_vxworks.rs
+++ b/compiler/rustc_target/src/spec/aarch64_wrs_vxworks.rs
@@ -1,14 +1,11 @@
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let mut base = super::vxworks_base::opts();
-    base.max_atomic_width = Some(128);
-
     Target {
         llvm_target: "aarch64-unknown-linux-gnu".to_string(),
         pointer_width: 64,
         data_layout: "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128".to_string(),
         arch: "aarch64".to_string(),
-        options: TargetOptions { unsupported_abis: super::arm_base::unsupported_abis(), ..base },
+        options: TargetOptions { max_atomic_width: Some(128), ..super::vxworks_base::opts() },
     }
 }
diff --git a/compiler/rustc_target/src/spec/abi.rs b/compiler/rustc_target/src/spec/abi.rs
index a026a623f78..ee36090c549 100644
--- a/compiler/rustc_target/src/spec/abi.rs
+++ b/compiler/rustc_target/src/spec/abi.rs
@@ -8,16 +8,11 @@ mod tests;
 #[derive(PartialEq, Eq, PartialOrd, Ord, Hash, Clone, Copy, Debug)]
 #[derive(HashStable_Generic, Encodable, Decodable)]
 pub enum Abi {
-    // Multiplatform / generic ABIs
-    //
-    // These ABIs come first because every time we add a new ABI, we
-    // have to re-bless all the hashing tests. These are used in many
-    // places, so giving them stable values reduces test churn. The
-    // specific values are meaningless.
+    // Some of the ABIs come first because every time we add a new ABI, we have to re-bless all the
+    // hashing tests. These are used in many places, so giving them stable values reduces test
+    // churn. The specific values are meaningless.
     Rust,
     C { unwind: bool },
-
-    // Single platform ABIs
     Cdecl,
     Stdcall { unwind: bool },
     Fastcall,
@@ -35,8 +30,6 @@ pub enum Abi {
     AvrNonBlockingInterrupt,
     CCmseNonSecureCall,
     Wasm,
-
-    // Multiplatform / generic ABIs
     System { unwind: bool },
     RustIntrinsic,
     RustCall,
@@ -50,48 +43,38 @@ pub struct AbiData {
 
     /// Name of this ABI as we like it called.
     name: &'static str,
-
-    /// A generic ABI is supported on all platforms.
-    generic: bool,
 }
 
 #[allow(non_upper_case_globals)]
 const AbiDatas: &[AbiData] = &[
-    // Cross-platform ABIs
-    AbiData { abi: Abi::Rust, name: "Rust", generic: true },
-    AbiData { abi: Abi::C { unwind: false }, name: "C", generic: true },
-    AbiData { abi: Abi::C { unwind: true }, name: "C-unwind", generic: true },
-    // Platform-specific ABIs
-    AbiData { abi: Abi::Cdecl, name: "cdecl", generic: false },
-    AbiData { abi: Abi::Stdcall { unwind: false }, name: "stdcall", generic: false },
-    AbiData { abi: Abi::Stdcall { unwind: true }, name: "stdcall-unwind", generic: false },
-    AbiData { abi: Abi::Fastcall, name: "fastcall", generic: false },
-    AbiData { abi: Abi::Vectorcall, name: "vectorcall", generic: false },
-    AbiData { abi: Abi::Thiscall { unwind: false }, name: "thiscall", generic: false },
-    AbiData { abi: Abi::Thiscall { unwind: true }, name: "thiscall-unwind", generic: false },
-    AbiData { abi: Abi::Aapcs, name: "aapcs", generic: false },
-    AbiData { abi: Abi::Win64, name: "win64", generic: false },
-    AbiData { abi: Abi::SysV64, name: "sysv64", generic: false },
-    AbiData { abi: Abi::PtxKernel, name: "ptx-kernel", generic: false },
-    AbiData { abi: Abi::Msp430Interrupt, name: "msp430-interrupt", generic: false },
-    AbiData { abi: Abi::X86Interrupt, name: "x86-interrupt", generic: false },
-    AbiData { abi: Abi::AmdGpuKernel, name: "amdgpu-kernel", generic: false },
-    AbiData { abi: Abi::EfiApi, name: "efiapi", generic: false },
-    AbiData { abi: Abi::AvrInterrupt, name: "avr-interrupt", generic: false },
-    AbiData {
-        abi: Abi::AvrNonBlockingInterrupt,
-        name: "avr-non-blocking-interrupt",
-        generic: false,
-    },
-    AbiData { abi: Abi::CCmseNonSecureCall, name: "C-cmse-nonsecure-call", generic: false },
-    AbiData { abi: Abi::Wasm, name: "wasm", generic: false },
-    // Cross-platform ABIs
-    AbiData { abi: Abi::System { unwind: false }, name: "system", generic: true },
-    AbiData { abi: Abi::System { unwind: true }, name: "system-unwind", generic: true },
-    AbiData { abi: Abi::RustIntrinsic, name: "rust-intrinsic", generic: true },
-    AbiData { abi: Abi::RustCall, name: "rust-call", generic: true },
-    AbiData { abi: Abi::PlatformIntrinsic, name: "platform-intrinsic", generic: true },
-    AbiData { abi: Abi::Unadjusted, name: "unadjusted", generic: true },
+    AbiData { abi: Abi::Rust, name: "Rust" },
+    AbiData { abi: Abi::C { unwind: false }, name: "C" },
+    AbiData { abi: Abi::C { unwind: true }, name: "C-unwind" },
+    AbiData { abi: Abi::Cdecl, name: "cdecl" },
+    AbiData { abi: Abi::Stdcall { unwind: false }, name: "stdcall" },
+    AbiData { abi: Abi::Stdcall { unwind: true }, name: "stdcall-unwind" },
+    AbiData { abi: Abi::Fastcall, name: "fastcall" },
+    AbiData { abi: Abi::Vectorcall, name: "vectorcall" },
+    AbiData { abi: Abi::Thiscall { unwind: false }, name: "thiscall" },
+    AbiData { abi: Abi::Thiscall { unwind: true }, name: "thiscall-unwind" },
+    AbiData { abi: Abi::Aapcs, name: "aapcs" },
+    AbiData { abi: Abi::Win64, name: "win64" },
+    AbiData { abi: Abi::SysV64, name: "sysv64" },
+    AbiData { abi: Abi::PtxKernel, name: "ptx-kernel" },
+    AbiData { abi: Abi::Msp430Interrupt, name: "msp430-interrupt" },
+    AbiData { abi: Abi::X86Interrupt, name: "x86-interrupt" },
+    AbiData { abi: Abi::AmdGpuKernel, name: "amdgpu-kernel" },
+    AbiData { abi: Abi::EfiApi, name: "efiapi" },
+    AbiData { abi: Abi::AvrInterrupt, name: "avr-interrupt" },
+    AbiData { abi: Abi::AvrNonBlockingInterrupt, name: "avr-non-blocking-interrupt" },
+    AbiData { abi: Abi::CCmseNonSecureCall, name: "C-cmse-nonsecure-call" },
+    AbiData { abi: Abi::Wasm, name: "wasm" },
+    AbiData { abi: Abi::System { unwind: false }, name: "system" },
+    AbiData { abi: Abi::System { unwind: true }, name: "system-unwind" },
+    AbiData { abi: Abi::RustIntrinsic, name: "rust-intrinsic" },
+    AbiData { abi: Abi::RustCall, name: "rust-call" },
+    AbiData { abi: Abi::PlatformIntrinsic, name: "platform-intrinsic" },
+    AbiData { abi: Abi::Unadjusted, name: "unadjusted" },
 ];
 
 /// Returns the ABI with the given name (if any).
@@ -163,10 +146,6 @@ impl Abi {
     pub fn name(self) -> &'static str {
         self.data().name
     }
-
-    pub fn generic(self) -> bool {
-        self.data().generic
-    }
 }
 
 impl fmt::Display for Abi {
diff --git a/compiler/rustc_target/src/spec/arm_base.rs b/compiler/rustc_target/src/spec/arm_base.rs
deleted file mode 100644
index 01f573313c9..00000000000
--- a/compiler/rustc_target/src/spec/arm_base.rs
+++ /dev/null
@@ -1,15 +0,0 @@
-use crate::spec::abi::Abi;
-
-// All the calling conventions trigger an assertion(Unsupported calling convention) in llvm on arm
-pub fn unsupported_abis() -> Vec<Abi> {
-    vec![
-        Abi::Stdcall { unwind: false },
-        Abi::Stdcall { unwind: true },
-        Abi::Fastcall,
-        Abi::Vectorcall,
-        Abi::Thiscall { unwind: false },
-        Abi::Thiscall { unwind: true },
-        Abi::Win64,
-        Abi::SysV64,
-    ]
-}
diff --git a/compiler/rustc_target/src/spec/arm_linux_androideabi.rs b/compiler/rustc_target/src/spec/arm_linux_androideabi.rs
index 43537569e7d..f2430830afc 100644
--- a/compiler/rustc_target/src/spec/arm_linux_androideabi.rs
+++ b/compiler/rustc_target/src/spec/arm_linux_androideabi.rs
@@ -1,16 +1,16 @@
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let mut base = super::android_base::opts();
-    // https://developer.android.com/ndk/guides/abis.html#armeabi
-    base.features = "+strict-align,+v5te".to_string();
-    base.max_atomic_width = Some(32);
-
     Target {
         llvm_target: "arm-linux-androideabi".to_string(),
         pointer_width: 32,
         data_layout: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
-        options: TargetOptions { unsupported_abis: super::arm_base::unsupported_abis(), ..base },
+        options: TargetOptions {
+            // https://developer.android.com/ndk/guides/abis.html#armeabi
+            features: "+strict-align,+v5te".to_string(),
+            max_atomic_width: Some(32),
+            ..super::android_base::opts()
+        },
     }
 }
diff --git a/compiler/rustc_target/src/spec/arm_unknown_linux_gnueabi.rs b/compiler/rustc_target/src/spec/arm_unknown_linux_gnueabi.rs
index c41cf6e521a..225db0032a8 100644
--- a/compiler/rustc_target/src/spec/arm_unknown_linux_gnueabi.rs
+++ b/compiler/rustc_target/src/spec/arm_unknown_linux_gnueabi.rs
@@ -1,19 +1,16 @@
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let mut base = super::linux_gnu_base::opts();
-    base.max_atomic_width = Some(64);
     Target {
         llvm_target: "arm-unknown-linux-gnueabi".to_string(),
         pointer_width: 32,
         data_layout: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
-
         options: TargetOptions {
             features: "+strict-align,+v6".to_string(),
-            unsupported_abis: super::arm_base::unsupported_abis(),
+            max_atomic_width: Some(64),
             mcount: "\u{1}__gnu_mcount_nc".to_string(),
-            ..base
+            ..super::linux_gnu_base::opts()
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/arm_unknown_linux_gnueabihf.rs b/compiler/rustc_target/src/spec/arm_unknown_linux_gnueabihf.rs
index f2143966c1d..33703195ee7 100644
--- a/compiler/rustc_target/src/spec/arm_unknown_linux_gnueabihf.rs
+++ b/compiler/rustc_target/src/spec/arm_unknown_linux_gnueabihf.rs
@@ -1,19 +1,16 @@
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let mut base = super::linux_gnu_base::opts();
-    base.max_atomic_width = Some(64);
     Target {
         llvm_target: "arm-unknown-linux-gnueabihf".to_string(),
         pointer_width: 32,
         data_layout: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
-
         options: TargetOptions {
             features: "+strict-align,+v6,+vfp2,-d32".to_string(),
-            unsupported_abis: super::arm_base::unsupported_abis(),
+            max_atomic_width: Some(64),
             mcount: "\u{1}__gnu_mcount_nc".to_string(),
-            ..base
+            ..super::linux_gnu_base::opts()
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/arm_unknown_linux_musleabi.rs b/compiler/rustc_target/src/spec/arm_unknown_linux_musleabi.rs
index 53ff1001c20..850844993f9 100644
--- a/compiler/rustc_target/src/spec/arm_unknown_linux_musleabi.rs
+++ b/compiler/rustc_target/src/spec/arm_unknown_linux_musleabi.rs
@@ -1,12 +1,6 @@
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let mut base = super::linux_musl_base::opts();
-
-    // Most of these settings are copied from the arm_unknown_linux_gnueabi
-    // target.
-    base.features = "+strict-align,+v6".to_string();
-    base.max_atomic_width = Some(64);
     Target {
         // It's important we use "gnueabi" and not "musleabi" here. LLVM uses it
         // to determine the calling convention and float ABI, and it doesn't
@@ -16,9 +10,12 @@ pub fn target() -> Target {
         data_layout: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
         options: TargetOptions {
-            unsupported_abis: super::arm_base::unsupported_abis(),
+            // Most of these settings are copied from the arm_unknown_linux_gnueabi
+            // target.
+            features: "+strict-align,+v6".to_string(),
+            max_atomic_width: Some(64),
             mcount: "\u{1}mcount".to_string(),
-            ..base
+            ..super::linux_musl_base::opts()
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/arm_unknown_linux_musleabihf.rs b/compiler/rustc_target/src/spec/arm_unknown_linux_musleabihf.rs
index 6d8a5f9f88b..ff69c462e8e 100644
--- a/compiler/rustc_target/src/spec/arm_unknown_linux_musleabihf.rs
+++ b/compiler/rustc_target/src/spec/arm_unknown_linux_musleabihf.rs
@@ -1,12 +1,6 @@
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let mut base = super::linux_musl_base::opts();
-
-    // Most of these settings are copied from the arm_unknown_linux_gnueabihf
-    // target.
-    base.features = "+strict-align,+v6,+vfp2,-d32".to_string();
-    base.max_atomic_width = Some(64);
     Target {
         // It's important we use "gnueabihf" and not "musleabihf" here. LLVM
         // uses it to determine the calling convention and float ABI, and it
@@ -16,9 +10,12 @@ pub fn target() -> Target {
         data_layout: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
         options: TargetOptions {
-            unsupported_abis: super::arm_base::unsupported_abis(),
+            // Most of these settings are copied from the arm_unknown_linux_gnueabihf
+            // target.
+            features: "+strict-align,+v6,+vfp2,-d32".to_string(),
+            max_atomic_width: Some(64),
             mcount: "\u{1}mcount".to_string(),
-            ..base
+            ..super::linux_musl_base::opts()
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/armebv7r_none_eabi.rs b/compiler/rustc_target/src/spec/armebv7r_none_eabi.rs
index 255740cb9c0..547f48c5d3b 100644
--- a/compiler/rustc_target/src/spec/armebv7r_none_eabi.rs
+++ b/compiler/rustc_target/src/spec/armebv7r_none_eabi.rs
@@ -10,7 +10,6 @@ pub fn target() -> Target {
         pointer_width: 32,
         data_layout: "E-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
-
         options: TargetOptions {
             endian: Endian::Big,
             linker_flavor: LinkerFlavor::Lld(LldFlavor::Ld),
@@ -19,7 +18,6 @@ pub fn target() -> Target {
             relocation_model: RelocModel::Static,
             panic_strategy: PanicStrategy::Abort,
             max_atomic_width: Some(32),
-            unsupported_abis: super::arm_base::unsupported_abis(),
             emit_debug_gdb_scripts: false,
             ..Default::default()
         },
diff --git a/compiler/rustc_target/src/spec/armebv7r_none_eabihf.rs b/compiler/rustc_target/src/spec/armebv7r_none_eabihf.rs
index eb82e4d17b0..f4f61e87ab9 100644
--- a/compiler/rustc_target/src/spec/armebv7r_none_eabihf.rs
+++ b/compiler/rustc_target/src/spec/armebv7r_none_eabihf.rs
@@ -10,7 +10,6 @@ pub fn target() -> Target {
         pointer_width: 32,
         data_layout: "E-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
-
         options: TargetOptions {
             endian: Endian::Big,
             linker_flavor: LinkerFlavor::Lld(LldFlavor::Ld),
@@ -20,7 +19,6 @@ pub fn target() -> Target {
             panic_strategy: PanicStrategy::Abort,
             features: "+vfp3,-d32,-fp16".to_string(),
             max_atomic_width: Some(32),
-            unsupported_abis: super::arm_base::unsupported_abis(),
             emit_debug_gdb_scripts: false,
             ..Default::default()
         },
diff --git a/compiler/rustc_target/src/spec/armv4t_unknown_linux_gnueabi.rs b/compiler/rustc_target/src/spec/armv4t_unknown_linux_gnueabi.rs
index e1ba72bf83b..8a289fee781 100644
--- a/compiler/rustc_target/src/spec/armv4t_unknown_linux_gnueabi.rs
+++ b/compiler/rustc_target/src/spec/armv4t_unknown_linux_gnueabi.rs
@@ -1,21 +1,18 @@
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let base = super::linux_gnu_base::opts();
     Target {
         llvm_target: "armv4t-unknown-linux-gnueabi".to_string(),
         pointer_width: 32,
         data_layout: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
-
         options: TargetOptions {
             features: "+soft-float,+strict-align".to_string(),
             // Atomic operations provided by compiler-builtins
             max_atomic_width: Some(32),
-            unsupported_abis: super::arm_base::unsupported_abis(),
             mcount: "\u{1}__gnu_mcount_nc".to_string(),
             has_thumb_interworking: true,
-            ..base
+            ..super::linux_gnu_base::opts()
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/armv5te_unknown_linux_gnueabi.rs b/compiler/rustc_target/src/spec/armv5te_unknown_linux_gnueabi.rs
index 3ac8d53564d..177ab453b04 100644
--- a/compiler/rustc_target/src/spec/armv5te_unknown_linux_gnueabi.rs
+++ b/compiler/rustc_target/src/spec/armv5te_unknown_linux_gnueabi.rs
@@ -1,21 +1,18 @@
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let base = super::linux_gnu_base::opts();
     Target {
         llvm_target: "armv5te-unknown-linux-gnueabi".to_string(),
         pointer_width: 32,
         data_layout: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
-
         options: TargetOptions {
             features: "+soft-float,+strict-align".to_string(),
             // Atomic operations provided by compiler-builtins
             max_atomic_width: Some(32),
-            unsupported_abis: super::arm_base::unsupported_abis(),
             mcount: "\u{1}__gnu_mcount_nc".to_string(),
             has_thumb_interworking: true,
-            ..base
+            ..super::linux_gnu_base::opts()
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/armv5te_unknown_linux_musleabi.rs b/compiler/rustc_target/src/spec/armv5te_unknown_linux_musleabi.rs
index 40d405c30a2..1f084443bd9 100644
--- a/compiler/rustc_target/src/spec/armv5te_unknown_linux_musleabi.rs
+++ b/compiler/rustc_target/src/spec/armv5te_unknown_linux_musleabi.rs
@@ -1,8 +1,8 @@
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let base = super::linux_musl_base::opts();
     Target {
+        // FIXME: this comment below does not seem applicable?
         // It's important we use "gnueabihf" and not "musleabihf" here. LLVM
         // uses it to determine the calling convention and float ABI, and LLVM
         // doesn't support the "musleabihf" value.
@@ -10,15 +10,13 @@ pub fn target() -> Target {
         pointer_width: 32,
         data_layout: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
-
         options: TargetOptions {
             features: "+soft-float,+strict-align".to_string(),
             // Atomic operations provided by compiler-builtins
             max_atomic_width: Some(32),
-            unsupported_abis: super::arm_base::unsupported_abis(),
             mcount: "\u{1}mcount".to_string(),
             has_thumb_interworking: true,
-            ..base
+            ..super::linux_musl_base::opts()
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/armv5te_unknown_linux_uclibceabi.rs b/compiler/rustc_target/src/spec/armv5te_unknown_linux_uclibceabi.rs
index 3eb0f4db833..4e5b714bded 100644
--- a/compiler/rustc_target/src/spec/armv5te_unknown_linux_uclibceabi.rs
+++ b/compiler/rustc_target/src/spec/armv5te_unknown_linux_uclibceabi.rs
@@ -10,10 +10,8 @@ pub fn target() -> Target {
             features: "+soft-float,+strict-align".to_string(),
             // Atomic operations provided by compiler-builtins
             max_atomic_width: Some(32),
-            unsupported_abis: super::arm_base::unsupported_abis(),
             mcount: "\u{1}__gnu_mcount_nc".to_string(),
             has_thumb_interworking: true,
-
             ..super::linux_uclibc_base::opts()
         },
     }
diff --git a/compiler/rustc_target/src/spec/armv6_unknown_freebsd.rs b/compiler/rustc_target/src/spec/armv6_unknown_freebsd.rs
index a149bd983b7..08fc51e8a8b 100644
--- a/compiler/rustc_target/src/spec/armv6_unknown_freebsd.rs
+++ b/compiler/rustc_target/src/spec/armv6_unknown_freebsd.rs
@@ -1,20 +1,17 @@
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let base = super::freebsd_base::opts();
     Target {
         llvm_target: "armv6-unknown-freebsd-gnueabihf".to_string(),
         pointer_width: 32,
         data_layout: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
-
         options: TargetOptions {
             env: "gnueabihf".to_string(),
             features: "+v6,+vfp2,-d32".to_string(),
             max_atomic_width: Some(64),
-            unsupported_abis: super::arm_base::unsupported_abis(),
             mcount: "\u{1}__gnu_mcount_nc".to_string(),
-            ..base
+            ..super::freebsd_base::opts()
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/armv6_unknown_netbsd_eabihf.rs b/compiler/rustc_target/src/spec/armv6_unknown_netbsd_eabihf.rs
index 6c81a458b9b..b109aa1e1ab 100644
--- a/compiler/rustc_target/src/spec/armv6_unknown_netbsd_eabihf.rs
+++ b/compiler/rustc_target/src/spec/armv6_unknown_netbsd_eabihf.rs
@@ -1,20 +1,17 @@
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let mut base = super::netbsd_base::opts();
-    base.max_atomic_width = Some(64);
     Target {
         llvm_target: "armv6-unknown-netbsdelf-eabihf".to_string(),
         pointer_width: 32,
         data_layout: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
-
         options: TargetOptions {
             env: "eabihf".to_string(),
             features: "+v6,+vfp2,-d32".to_string(),
-            unsupported_abis: super::arm_base::unsupported_abis(),
+            max_atomic_width: Some(64),
             mcount: "__mcount".to_string(),
-            ..base
+            ..super::netbsd_base::opts()
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/armv7_apple_ios.rs b/compiler/rustc_target/src/spec/armv7_apple_ios.rs
index 051a394657c..2f228688f43 100644
--- a/compiler/rustc_target/src/spec/armv7_apple_ios.rs
+++ b/compiler/rustc_target/src/spec/armv7_apple_ios.rs
@@ -2,7 +2,6 @@ use super::apple_sdk_base::{opts, Arch};
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let base = opts("ios", Arch::Armv7);
     Target {
         llvm_target: "armv7-apple-ios".to_string(),
         pointer_width: 32,
@@ -11,8 +10,7 @@ pub fn target() -> Target {
         options: TargetOptions {
             features: "+v7,+vfp3,+neon".to_string(),
             max_atomic_width: Some(64),
-            unsupported_abis: super::arm_base::unsupported_abis(),
-            ..base
+            ..opts("ios", Arch::Armv7)
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/armv7_linux_androideabi.rs b/compiler/rustc_target/src/spec/armv7_linux_androideabi.rs
index 02a1191463e..821080ec07d 100644
--- a/compiler/rustc_target/src/spec/armv7_linux_androideabi.rs
+++ b/compiler/rustc_target/src/spec/armv7_linux_androideabi.rs
@@ -10,15 +10,16 @@ use crate::spec::{LinkerFlavor, Target, TargetOptions};
 
 pub fn target() -> Target {
     let mut base = super::android_base::opts();
-    base.features = "+v7,+thumb-mode,+thumb2,+vfp3,-d32,-neon".to_string();
-    base.max_atomic_width = Some(64);
     base.pre_link_args.entry(LinkerFlavor::Gcc).or_default().push("-march=armv7-a".to_string());
-
     Target {
         llvm_target: "armv7-none-linux-android".to_string(),
         pointer_width: 32,
         data_layout: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
-        options: TargetOptions { unsupported_abis: super::arm_base::unsupported_abis(), ..base },
+        options: TargetOptions {
+            features: "+v7,+thumb-mode,+thumb2,+vfp3,-d32,-neon".to_string(),
+            max_atomic_width: Some(64),
+            ..base
+        },
     }
 }
diff --git a/compiler/rustc_target/src/spec/armv7_unknown_freebsd.rs b/compiler/rustc_target/src/spec/armv7_unknown_freebsd.rs
index 6f24c6818fc..190d3bb691a 100644
--- a/compiler/rustc_target/src/spec/armv7_unknown_freebsd.rs
+++ b/compiler/rustc_target/src/spec/armv7_unknown_freebsd.rs
@@ -1,20 +1,17 @@
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let base = super::freebsd_base::opts();
     Target {
         llvm_target: "armv7-unknown-freebsd-gnueabihf".to_string(),
         pointer_width: 32,
         data_layout: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
-
         options: TargetOptions {
             env: "gnueabihf".to_string(),
             features: "+v7,+vfp3,-d32,+thumb2,-neon".to_string(),
             max_atomic_width: Some(64),
-            unsupported_abis: super::arm_base::unsupported_abis(),
             mcount: "\u{1}__gnu_mcount_nc".to_string(),
-            ..base
+            ..super::freebsd_base::opts()
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/armv7_unknown_linux_gnueabi.rs b/compiler/rustc_target/src/spec/armv7_unknown_linux_gnueabi.rs
index f6fe88de37c..088a8cf7534 100644
--- a/compiler/rustc_target/src/spec/armv7_unknown_linux_gnueabi.rs
+++ b/compiler/rustc_target/src/spec/armv7_unknown_linux_gnueabi.rs
@@ -4,19 +4,16 @@ use crate::spec::{Target, TargetOptions};
 // hardfloat.
 
 pub fn target() -> Target {
-    let base = super::linux_gnu_base::opts();
     Target {
         llvm_target: "armv7-unknown-linux-gnueabi".to_string(),
         pointer_width: 32,
         data_layout: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
-
         options: TargetOptions {
             features: "+v7,+thumb2,+soft-float,-neon".to_string(),
             max_atomic_width: Some(64),
-            unsupported_abis: super::arm_base::unsupported_abis(),
             mcount: "\u{1}__gnu_mcount_nc".to_string(),
-            ..base
+            ..super::linux_gnu_base::opts()
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/armv7_unknown_linux_gnueabihf.rs b/compiler/rustc_target/src/spec/armv7_unknown_linux_gnueabihf.rs
index 5f0f47dd397..521053ec2d3 100644
--- a/compiler/rustc_target/src/spec/armv7_unknown_linux_gnueabihf.rs
+++ b/compiler/rustc_target/src/spec/armv7_unknown_linux_gnueabihf.rs
@@ -4,20 +4,17 @@ use crate::spec::{Target, TargetOptions};
 // thumb-mode. See the thumbv7neon variant for enabling both.
 
 pub fn target() -> Target {
-    let base = super::linux_gnu_base::opts();
     Target {
         llvm_target: "armv7-unknown-linux-gnueabihf".to_string(),
         pointer_width: 32,
         data_layout: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
-
         options: TargetOptions {
             // Info about features at https://wiki.debian.org/ArmHardFloatPort
             features: "+v7,+vfp3,-d32,+thumb2,-neon".to_string(),
             max_atomic_width: Some(64),
-            unsupported_abis: super::arm_base::unsupported_abis(),
             mcount: "\u{1}__gnu_mcount_nc".to_string(),
-            ..base
+            ..super::linux_gnu_base::opts()
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/armv7_unknown_linux_musleabi.rs b/compiler/rustc_target/src/spec/armv7_unknown_linux_musleabi.rs
index c888fc2d4a3..0ee2c3e45e0 100644
--- a/compiler/rustc_target/src/spec/armv7_unknown_linux_musleabi.rs
+++ b/compiler/rustc_target/src/spec/armv7_unknown_linux_musleabi.rs
@@ -4,7 +4,6 @@ use crate::spec::{Target, TargetOptions};
 // hardfloat.
 
 pub fn target() -> Target {
-    let base = super::linux_musl_base::opts();
     // Most of these settings are copied from the armv7_unknown_linux_gnueabi
     // target.
     Target {
@@ -19,9 +18,8 @@ pub fn target() -> Target {
         options: TargetOptions {
             features: "+v7,+thumb2,+soft-float,-neon".to_string(),
             max_atomic_width: Some(64),
-            unsupported_abis: super::arm_base::unsupported_abis(),
             mcount: "\u{1}mcount".to_string(),
-            ..base
+            ..super::linux_musl_base::opts()
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/armv7_unknown_linux_musleabihf.rs b/compiler/rustc_target/src/spec/armv7_unknown_linux_musleabihf.rs
index 2432ea519a8..a6ce382c7a6 100644
--- a/compiler/rustc_target/src/spec/armv7_unknown_linux_musleabihf.rs
+++ b/compiler/rustc_target/src/spec/armv7_unknown_linux_musleabihf.rs
@@ -3,7 +3,6 @@ use crate::spec::{Target, TargetOptions};
 // This target is for musl Linux on ARMv7 without thumb-mode or NEON.
 
 pub fn target() -> Target {
-    let base = super::linux_musl_base::opts();
     Target {
         // It's important we use "gnueabihf" and not "musleabihf" here. LLVM
         // uses it to determine the calling convention and float ABI, and LLVM
@@ -18,9 +17,8 @@ pub fn target() -> Target {
         options: TargetOptions {
             features: "+v7,+vfp3,-d32,+thumb2,-neon".to_string(),
             max_atomic_width: Some(64),
-            unsupported_abis: super::arm_base::unsupported_abis(),
             mcount: "\u{1}mcount".to_string(),
-            ..base
+            ..super::linux_musl_base::opts()
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/armv7_unknown_netbsd_eabihf.rs b/compiler/rustc_target/src/spec/armv7_unknown_netbsd_eabihf.rs
index 4fae3a8d0bf..e509dcaddaa 100644
--- a/compiler/rustc_target/src/spec/armv7_unknown_netbsd_eabihf.rs
+++ b/compiler/rustc_target/src/spec/armv7_unknown_netbsd_eabihf.rs
@@ -1,20 +1,17 @@
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let base = super::netbsd_base::opts();
     Target {
         llvm_target: "armv7-unknown-netbsdelf-eabihf".to_string(),
         pointer_width: 32,
         data_layout: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
-
         options: TargetOptions {
             env: "eabihf".to_string(),
             features: "+v7,+vfp3,-d32,+thumb2,-neon".to_string(),
             max_atomic_width: Some(64),
-            unsupported_abis: super::arm_base::unsupported_abis(),
             mcount: "__mcount".to_string(),
-            ..base
+            ..super::netbsd_base::opts()
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/armv7_wrs_vxworks_eabihf.rs b/compiler/rustc_target/src/spec/armv7_wrs_vxworks_eabihf.rs
index 9fe7098a85f..0aabf2fe486 100644
--- a/compiler/rustc_target/src/spec/armv7_wrs_vxworks_eabihf.rs
+++ b/compiler/rustc_target/src/spec/armv7_wrs_vxworks_eabihf.rs
@@ -1,7 +1,6 @@
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let base = super::vxworks_base::opts();
     Target {
         llvm_target: "armv7-unknown-linux-gnueabihf".to_string(),
         pointer_width: 32,
@@ -11,8 +10,7 @@ pub fn target() -> Target {
             // Info about features at https://wiki.debian.org/ArmHardFloatPort
             features: "+v7,+vfp3,-d32,+thumb2,-neon".to_string(),
             max_atomic_width: Some(64),
-            unsupported_abis: super::arm_base::unsupported_abis(),
-            ..base
+            ..super::vxworks_base::opts()
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/armv7a_none_eabi.rs b/compiler/rustc_target/src/spec/armv7a_none_eabi.rs
index 74deab01916..bd703ee3e45 100644
--- a/compiler/rustc_target/src/spec/armv7a_none_eabi.rs
+++ b/compiler/rustc_target/src/spec/armv7a_none_eabi.rs
@@ -26,7 +26,6 @@ pub fn target() -> Target {
         disable_redzone: true,
         max_atomic_width: Some(64),
         panic_strategy: PanicStrategy::Abort,
-        unsupported_abis: super::arm_base::unsupported_abis(),
         emit_debug_gdb_scripts: false,
         ..Default::default()
     };
diff --git a/compiler/rustc_target/src/spec/armv7a_none_eabihf.rs b/compiler/rustc_target/src/spec/armv7a_none_eabihf.rs
index c5c720f5fbd..ad86ae1cedc 100644
--- a/compiler/rustc_target/src/spec/armv7a_none_eabihf.rs
+++ b/compiler/rustc_target/src/spec/armv7a_none_eabihf.rs
@@ -17,7 +17,6 @@ pub fn target() -> Target {
         disable_redzone: true,
         max_atomic_width: Some(64),
         panic_strategy: PanicStrategy::Abort,
-        unsupported_abis: super::arm_base::unsupported_abis(),
         emit_debug_gdb_scripts: false,
         ..Default::default()
     };
diff --git a/compiler/rustc_target/src/spec/armv7r_none_eabi.rs b/compiler/rustc_target/src/spec/armv7r_none_eabi.rs
index 3f49bd87869..c07d6adc37e 100644
--- a/compiler/rustc_target/src/spec/armv7r_none_eabi.rs
+++ b/compiler/rustc_target/src/spec/armv7r_none_eabi.rs
@@ -17,7 +17,6 @@ pub fn target() -> Target {
             relocation_model: RelocModel::Static,
             panic_strategy: PanicStrategy::Abort,
             max_atomic_width: Some(32),
-            unsupported_abis: super::arm_base::unsupported_abis(),
             emit_debug_gdb_scripts: false,
             ..Default::default()
         },
diff --git a/compiler/rustc_target/src/spec/armv7r_none_eabihf.rs b/compiler/rustc_target/src/spec/armv7r_none_eabihf.rs
index 9b2e8a8058f..fbf2f8e9b72 100644
--- a/compiler/rustc_target/src/spec/armv7r_none_eabihf.rs
+++ b/compiler/rustc_target/src/spec/armv7r_none_eabihf.rs
@@ -18,7 +18,6 @@ pub fn target() -> Target {
             panic_strategy: PanicStrategy::Abort,
             features: "+vfp3,-d32,-fp16".to_string(),
             max_atomic_width: Some(32),
-            unsupported_abis: super::arm_base::unsupported_abis(),
             emit_debug_gdb_scripts: false,
             ..Default::default()
         },
diff --git a/compiler/rustc_target/src/spec/armv7s_apple_ios.rs b/compiler/rustc_target/src/spec/armv7s_apple_ios.rs
index be74136a2d6..2a48e7b6214 100644
--- a/compiler/rustc_target/src/spec/armv7s_apple_ios.rs
+++ b/compiler/rustc_target/src/spec/armv7s_apple_ios.rs
@@ -2,7 +2,6 @@ use super::apple_sdk_base::{opts, Arch};
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let base = opts("ios", Arch::Armv7s);
     Target {
         llvm_target: "armv7s-apple-ios".to_string(),
         pointer_width: 32,
@@ -11,8 +10,7 @@ pub fn target() -> Target {
         options: TargetOptions {
             features: "+v7,+vfp4,+neon".to_string(),
             max_atomic_width: Some(64),
-            unsupported_abis: super::arm_base::unsupported_abis(),
-            ..base
+            ..opts("ios", Arch::Armv7s)
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/bpf_base.rs b/compiler/rustc_target/src/spec/bpf_base.rs
index 764cc735d75..4fa6e12f5ba 100644
--- a/compiler/rustc_target/src/spec/bpf_base.rs
+++ b/compiler/rustc_target/src/spec/bpf_base.rs
@@ -1,5 +1,5 @@
+use crate::abi::Endian;
 use crate::spec::{LinkerFlavor, MergeFunctions, PanicStrategy, TargetOptions};
-use crate::{abi::Endian, spec::abi::Abi};
 
 pub fn opts(endian: Endian) -> TargetOptions {
     TargetOptions {
@@ -21,22 +21,6 @@ pub fn opts(endian: Endian) -> TargetOptions {
         requires_lto: false,
         singlethread: true,
         max_atomic_width: Some(64),
-        unsupported_abis: vec![
-            Abi::Cdecl,
-            Abi::Stdcall { unwind: false },
-            Abi::Stdcall { unwind: true },
-            Abi::Fastcall,
-            Abi::Vectorcall,
-            Abi::Thiscall { unwind: false },
-            Abi::Thiscall { unwind: true },
-            Abi::Aapcs,
-            Abi::Win64,
-            Abi::SysV64,
-            Abi::PtxKernel,
-            Abi::Msp430Interrupt,
-            Abi::X86Interrupt,
-            Abi::AmdGpuKernel,
-        ],
         ..Default::default()
     }
 }
diff --git a/compiler/rustc_target/src/spec/mipsel_unknown_none.rs b/compiler/rustc_target/src/spec/mipsel_unknown_none.rs
index 110c8dd80ea..5955baa31db 100644
--- a/compiler/rustc_target/src/spec/mipsel_unknown_none.rs
+++ b/compiler/rustc_target/src/spec/mipsel_unknown_none.rs
@@ -2,7 +2,6 @@
 //!
 //! Can be used for MIPS M4K core (e.g. on PIC32MX devices)
 
-use crate::spec::abi::Abi;
 use crate::spec::{LinkerFlavor, LldFlavor, RelocModel};
 use crate::spec::{PanicStrategy, Target, TargetOptions};
 
@@ -22,16 +21,6 @@ pub fn target() -> Target {
             linker: Some("rust-lld".to_owned()),
             panic_strategy: PanicStrategy::Abort,
             relocation_model: RelocModel::Static,
-            unsupported_abis: vec![
-                Abi::Stdcall { unwind: false },
-                Abi::Stdcall { unwind: true },
-                Abi::Fastcall,
-                Abi::Vectorcall,
-                Abi::Thiscall { unwind: false },
-                Abi::Thiscall { unwind: true },
-                Abi::Win64,
-                Abi::SysV64,
-            ],
             emit_debug_gdb_scripts: false,
             ..Default::default()
         },
diff --git a/compiler/rustc_target/src/spec/mod.rs b/compiler/rustc_target/src/spec/mod.rs
index cfdae9623f3..0a5f8c17c63 100644
--- a/compiler/rustc_target/src/spec/mod.rs
+++ b/compiler/rustc_target/src/spec/mod.rs
@@ -55,7 +55,6 @@ pub mod crt_objects;
 mod android_base;
 mod apple_base;
 mod apple_sdk_base;
-mod arm_base;
 mod avr_gnu_base;
 mod bpf_base;
 mod dragonfly_base;
@@ -75,7 +74,6 @@ mod msvc_base;
 mod netbsd_base;
 mod openbsd_base;
 mod redox_base;
-mod riscv_base;
 mod solaris_base;
 mod thumb_base;
 mod uefi_msvc_base;
@@ -1226,11 +1224,6 @@ pub struct TargetOptions {
     /// Panic strategy: "unwind" or "abort"
     pub panic_strategy: PanicStrategy,
 
-    /// A list of ABIs unsupported by the current target. Note that generic ABIs
-    /// are considered to be supported on all platforms and cannot be marked
-    /// unsupported.
-    pub unsupported_abis: Vec<Abi>,
-
     /// Whether or not linking dylibs to a static CRT is allowed.
     pub crt_static_allows_dylibs: bool,
     /// Whether or not the CRT is statically linked by default.
@@ -1412,7 +1405,6 @@ impl Default for TargetOptions {
             max_atomic_width: None,
             atomic_cas: true,
             panic_strategy: PanicStrategy::Unwind,
-            unsupported_abis: vec![],
             crt_static_allows_dylibs: false,
             crt_static_default: false,
             crt_static_respected: false,
@@ -1465,40 +1457,88 @@ impl Target {
     /// Given a function ABI, turn it into the correct ABI for this target.
     pub fn adjust_abi(&self, abi: Abi) -> Abi {
         match abi {
-            Abi::System { unwind } => {
-                if self.is_like_windows && self.arch == "x86" {
-                    Abi::Stdcall { unwind }
-                } else {
-                    Abi::C { unwind }
-                }
-            }
-            // These ABI kinds are ignored on non-x86 Windows targets.
-            // See https://docs.microsoft.com/en-us/cpp/cpp/argument-passing-and-naming-conventions
-            // and the individual pages for __stdcall et al.
-            Abi::Stdcall { unwind } | Abi::Thiscall { unwind } => {
-                if self.is_like_windows && self.arch != "x86" { Abi::C { unwind } } else { abi }
-            }
-            Abi::Fastcall | Abi::Vectorcall => {
-                if self.is_like_windows && self.arch != "x86" {
-                    Abi::C { unwind: false }
-                } else {
-                    abi
-                }
-            }
-            Abi::EfiApi => {
-                if self.arch == "x86_64" {
-                    Abi::Win64
-                } else {
-                    Abi::C { unwind: false }
-                }
+            Abi::C { .. } => self.default_adjusted_cabi.unwrap_or(abi),
+            Abi::System { unwind } if self.is_like_windows && self.arch == "x86" => {
+                Abi::Stdcall { unwind }
             }
+            Abi::System { unwind } => Abi::C { unwind },
+            Abi::EfiApi if self.arch == "x86_64" => Abi::Win64,
+            Abi::EfiApi => Abi::C { unwind: false },
 
-            Abi::C { unwind } => self.default_adjusted_cabi.unwrap_or(Abi::C { unwind }),
+            // See commentary in `is_abi_supported`.
+            Abi::Stdcall { .. } | Abi::Thiscall { .. } if self.arch == "x86" => abi,
+            Abi::Stdcall { unwind } | Abi::Thiscall { unwind } => Abi::C { unwind },
+            Abi::Fastcall if self.arch == "x86" => abi,
+            Abi::Vectorcall if ["x86", "x86_64"].contains(&&self.arch[..]) => abi,
+            Abi::Fastcall | Abi::Vectorcall => Abi::C { unwind: false },
 
             abi => abi,
         }
     }
 
+    /// Returns a None if the UNSUPPORTED_CALLING_CONVENTIONS lint should be emitted
+    pub fn is_abi_supported(&self, abi: Abi) -> Option<bool> {
+        use Abi::*;
+        Some(match abi {
+            Rust
+            | C { .. }
+            | System { .. }
+            | RustIntrinsic
+            | RustCall
+            | PlatformIntrinsic
+            | Unadjusted
+            | Cdecl
+            | EfiApi => true,
+            X86Interrupt => ["x86", "x86_64"].contains(&&self.arch[..]),
+            Aapcs | CCmseNonSecureCall => ["arm", "aarch64"].contains(&&self.arch[..]),
+            Win64 | SysV64 => self.arch == "x86_64",
+            PtxKernel => self.arch == "nvptx64",
+            Msp430Interrupt => self.arch == "msp430",
+            AmdGpuKernel => self.arch == "amdgcn",
+            AvrInterrupt | AvrNonBlockingInterrupt => self.arch == "avr",
+            Wasm => ["wasm32", "wasm64"].contains(&&self.arch[..]),
+            // On windows these fall-back to platform native calling convention (C) when the
+            // architecture is not supported.
+            //
+            // This is I believe a historical accident that has occurred as part of Microsoft
+            // striving to allow most of the code to "just" compile when support for 64-bit x86
+            // was added and then later again, when support for ARM architectures was added.
+            //
+            // This is well documented across MSDN. Support for this in Rust has been added in
+            // #54576. This makes much more sense in context of Microsoft's C++ than it does in
+            // Rust, but there isn't much leeway remaining here to change it back at the time this
+            // comment has been written.
+            //
+            // Following are the relevant excerpts from the MSDN documentation.
+            //
+            // > The __vectorcall calling convention is only supported in native code on x86 and
+            // x64 processors that include Streaming SIMD Extensions 2 (SSE2) and above.
+            // > ...
+            // > On ARM machines, __vectorcall is accepted and ignored by the compiler.
+            //
+            // -- https://docs.microsoft.com/en-us/cpp/cpp/vectorcall?view=msvc-160
+            //
+            // > On ARM and x64 processors, __stdcall is accepted and ignored by the compiler;
+            //
+            // -- https://docs.microsoft.com/en-us/cpp/cpp/stdcall?view=msvc-160
+            //
+            // > In most cases, keywords or compiler switches that specify an unsupported
+            // > convention on a particular platform are ignored, and the platform default
+            // > convention is used.
+            //
+            // -- https://docs.microsoft.com/en-us/cpp/cpp/argument-passing-and-naming-conventions
+            Stdcall { .. } | Fastcall | Thiscall { .. } | Vectorcall if self.is_like_windows => {
+                true
+            }
+            // Outside of Windows we want to only support these calling conventions for the
+            // architectures for which these calling conventions are actually well defined.
+            Stdcall { .. } | Fastcall | Thiscall { .. } if self.arch == "x86" => true,
+            Vectorcall if ["x86", "x86_64"].contains(&&self.arch[..]) => true,
+            // Return a `None` for other cases so that we know to emit a future compat lint.
+            Stdcall { .. } | Fastcall | Thiscall { .. } | Vectorcall => return None,
+        })
+    }
+
     /// Minimum integer size in bits that this target can perform atomic
     /// operations on.
     pub fn min_atomic_width(&self) -> u64 {
@@ -1511,10 +1551,6 @@ impl Target {
         self.max_atomic_width.unwrap_or_else(|| self.pointer_width.into())
     }
 
-    pub fn is_abi_supported(&self, abi: Abi) -> bool {
-        abi.generic() || !self.unsupported_abis.contains(&abi)
-    }
-
     /// Loads a target descriptor from a JSON object.
     pub fn from_json(mut obj: Json) -> Result<(Target, TargetWarnings), String> {
         // While ugly, this code must remain this way to retain
@@ -1974,36 +2010,6 @@ impl Target {
         key!(supported_sanitizers, SanitizerSet)?;
         key!(default_adjusted_cabi, Option<Abi>)?;
 
-        // NB: The old name is deprecated, but support for it is retained for
-        // compatibility.
-        for name in ["abi-blacklist", "unsupported-abis"].iter() {
-            if let Some(j) = obj.remove_key(name) {
-                if let Some(array) = Json::as_array(&j) {
-                    for name in array.iter().filter_map(|abi| abi.as_string()) {
-                        match lookup_abi(name) {
-                            Some(abi) => {
-                                if abi.generic() {
-                                    return Err(format!(
-                                        "The ABI \"{}\" is considered to be supported on all \
-                                        targets and cannot be marked unsupported",
-                                        abi
-                                    ));
-                                }
-
-                                base.unsupported_abis.push(abi)
-                            }
-                            None => {
-                                return Err(format!(
-                                    "Unknown ABI \"{}\" in target specification",
-                                    name
-                                ));
-                            }
-                        }
-                    }
-                }
-            }
-        }
-
         // Each field should have been read using `Json::remove_key` so any keys remaining are unused.
         let remaining_keys = obj.as_object().ok_or("Expected JSON object for target")?.keys();
         Ok((
@@ -2241,17 +2247,6 @@ impl ToJson for Target {
             d.insert("default-adjusted-cabi".to_string(), Abi::name(abi).to_json());
         }
 
-        if default.unsupported_abis != self.unsupported_abis {
-            d.insert(
-                "unsupported-abis".to_string(),
-                self.unsupported_abis
-                    .iter()
-                    .map(|&name| Abi::name(name).to_json())
-                    .collect::<Vec<_>>()
-                    .to_json(),
-            );
-        }
-
         Json::Object(d)
     }
 }
diff --git a/compiler/rustc_target/src/spec/nvptx64_nvidia_cuda.rs b/compiler/rustc_target/src/spec/nvptx64_nvidia_cuda.rs
index 97960a75b09..083262cf351 100644
--- a/compiler/rustc_target/src/spec/nvptx64_nvidia_cuda.rs
+++ b/compiler/rustc_target/src/spec/nvptx64_nvidia_cuda.rs
@@ -1,4 +1,3 @@
-use crate::spec::abi::Abi;
 use crate::spec::{LinkerFlavor, MergeFunctions, PanicStrategy, Target, TargetOptions};
 
 pub fn target() -> Target {
@@ -45,25 +44,6 @@ pub fn target() -> Target {
             // produce kernel functions that call other kernel functions.
             // This behavior is not supported by PTX ISA.
             merge_functions: MergeFunctions::Disabled,
-
-            // FIXME: enable compilation tests for the target and
-            // create the tests for this.
-            unsupported_abis: vec![
-                Abi::Cdecl,
-                Abi::Stdcall { unwind: false },
-                Abi::Stdcall { unwind: true },
-                Abi::Fastcall,
-                Abi::Vectorcall,
-                Abi::Thiscall { unwind: false },
-                Abi::Thiscall { unwind: true },
-                Abi::Aapcs,
-                Abi::Win64,
-                Abi::SysV64,
-                Abi::Msp430Interrupt,
-                Abi::X86Interrupt,
-                Abi::AmdGpuKernel,
-            ],
-
             ..Default::default()
         },
     }
diff --git a/compiler/rustc_target/src/spec/riscv32gc_unknown_linux_gnu.rs b/compiler/rustc_target/src/spec/riscv32gc_unknown_linux_gnu.rs
index cf5e0201d08..a9cdad1a8b1 100644
--- a/compiler/rustc_target/src/spec/riscv32gc_unknown_linux_gnu.rs
+++ b/compiler/rustc_target/src/spec/riscv32gc_unknown_linux_gnu.rs
@@ -7,7 +7,6 @@ pub fn target() -> Target {
         data_layout: "e-m:e-p:32:32-i64:64-n32-S128".to_string(),
         arch: "riscv32".to_string(),
         options: TargetOptions {
-            unsupported_abis: super::riscv_base::unsupported_abis(),
             code_model: Some(CodeModel::Medium),
             cpu: "generic-rv32".to_string(),
             features: "+m,+a,+f,+d,+c".to_string(),
diff --git a/compiler/rustc_target/src/spec/riscv32gc_unknown_linux_musl.rs b/compiler/rustc_target/src/spec/riscv32gc_unknown_linux_musl.rs
index e5fbd09297f..a64a82d55b9 100644
--- a/compiler/rustc_target/src/spec/riscv32gc_unknown_linux_musl.rs
+++ b/compiler/rustc_target/src/spec/riscv32gc_unknown_linux_musl.rs
@@ -7,7 +7,6 @@ pub fn target() -> Target {
         data_layout: "e-m:e-p:32:32-i64:64-n32-S128".to_string(),
         arch: "riscv32".to_string(),
         options: TargetOptions {
-            unsupported_abis: super::riscv_base::unsupported_abis(),
             code_model: Some(CodeModel::Medium),
             cpu: "generic-rv32".to_string(),
             features: "+m,+a,+f,+d,+c".to_string(),
diff --git a/compiler/rustc_target/src/spec/riscv32i_unknown_none_elf.rs b/compiler/rustc_target/src/spec/riscv32i_unknown_none_elf.rs
index 88a22f25ff4..16d37218f41 100644
--- a/compiler/rustc_target/src/spec/riscv32i_unknown_none_elf.rs
+++ b/compiler/rustc_target/src/spec/riscv32i_unknown_none_elf.rs
@@ -18,7 +18,6 @@ pub fn target() -> Target {
             panic_strategy: PanicStrategy::Abort,
             relocation_model: RelocModel::Static,
             emit_debug_gdb_scripts: false,
-            unsupported_abis: super::riscv_base::unsupported_abis(),
             eh_frame_header: false,
             ..Default::default()
         },
diff --git a/compiler/rustc_target/src/spec/riscv32imac_unknown_none_elf.rs b/compiler/rustc_target/src/spec/riscv32imac_unknown_none_elf.rs
index b406eec1e75..b53bae6cb56 100644
--- a/compiler/rustc_target/src/spec/riscv32imac_unknown_none_elf.rs
+++ b/compiler/rustc_target/src/spec/riscv32imac_unknown_none_elf.rs
@@ -18,7 +18,6 @@ pub fn target() -> Target {
             panic_strategy: PanicStrategy::Abort,
             relocation_model: RelocModel::Static,
             emit_debug_gdb_scripts: false,
-            unsupported_abis: super::riscv_base::unsupported_abis(),
             eh_frame_header: false,
             ..Default::default()
         },
diff --git a/compiler/rustc_target/src/spec/riscv32imc_unknown_none_elf.rs b/compiler/rustc_target/src/spec/riscv32imc_unknown_none_elf.rs
index 89d760e082f..9a23def1996 100644
--- a/compiler/rustc_target/src/spec/riscv32imc_unknown_none_elf.rs
+++ b/compiler/rustc_target/src/spec/riscv32imc_unknown_none_elf.rs
@@ -19,7 +19,6 @@ pub fn target() -> Target {
             panic_strategy: PanicStrategy::Abort,
             relocation_model: RelocModel::Static,
             emit_debug_gdb_scripts: false,
-            unsupported_abis: super::riscv_base::unsupported_abis(),
             eh_frame_header: false,
             ..Default::default()
         },
diff --git a/compiler/rustc_target/src/spec/riscv64gc_unknown_linux_gnu.rs b/compiler/rustc_target/src/spec/riscv64gc_unknown_linux_gnu.rs
index 84f28413fcb..02d44b5ed7e 100644
--- a/compiler/rustc_target/src/spec/riscv64gc_unknown_linux_gnu.rs
+++ b/compiler/rustc_target/src/spec/riscv64gc_unknown_linux_gnu.rs
@@ -7,7 +7,6 @@ pub fn target() -> Target {
         data_layout: "e-m:e-p:64:64-i64:64-i128:128-n64-S128".to_string(),
         arch: "riscv64".to_string(),
         options: TargetOptions {
-            unsupported_abis: super::riscv_base::unsupported_abis(),
             code_model: Some(CodeModel::Medium),
             cpu: "generic-rv64".to_string(),
             features: "+m,+a,+f,+d,+c".to_string(),
diff --git a/compiler/rustc_target/src/spec/riscv64gc_unknown_linux_musl.rs b/compiler/rustc_target/src/spec/riscv64gc_unknown_linux_musl.rs
index 0232b15e8c2..3754750e48d 100644
--- a/compiler/rustc_target/src/spec/riscv64gc_unknown_linux_musl.rs
+++ b/compiler/rustc_target/src/spec/riscv64gc_unknown_linux_musl.rs
@@ -7,7 +7,6 @@ pub fn target() -> Target {
         data_layout: "e-m:e-p:64:64-i64:64-i128:128-n64-S128".to_string(),
         arch: "riscv64".to_string(),
         options: TargetOptions {
-            unsupported_abis: super::riscv_base::unsupported_abis(),
             code_model: Some(CodeModel::Medium),
             cpu: "generic-rv64".to_string(),
             features: "+m,+a,+f,+d,+c".to_string(),
diff --git a/compiler/rustc_target/src/spec/riscv64gc_unknown_none_elf.rs b/compiler/rustc_target/src/spec/riscv64gc_unknown_none_elf.rs
index 481bce05a08..f527a6cd26d 100644
--- a/compiler/rustc_target/src/spec/riscv64gc_unknown_none_elf.rs
+++ b/compiler/rustc_target/src/spec/riscv64gc_unknown_none_elf.rs
@@ -20,7 +20,6 @@ pub fn target() -> Target {
             relocation_model: RelocModel::Static,
             code_model: Some(CodeModel::Medium),
             emit_debug_gdb_scripts: false,
-            unsupported_abis: super::riscv_base::unsupported_abis(),
             eh_frame_header: false,
             ..Default::default()
         },
diff --git a/compiler/rustc_target/src/spec/riscv64imac_unknown_none_elf.rs b/compiler/rustc_target/src/spec/riscv64imac_unknown_none_elf.rs
index 3e4afd446dd..8b1ba88e67f 100644
--- a/compiler/rustc_target/src/spec/riscv64imac_unknown_none_elf.rs
+++ b/compiler/rustc_target/src/spec/riscv64imac_unknown_none_elf.rs
@@ -19,7 +19,6 @@ pub fn target() -> Target {
             relocation_model: RelocModel::Static,
             code_model: Some(CodeModel::Medium),
             emit_debug_gdb_scripts: false,
-            unsupported_abis: super::riscv_base::unsupported_abis(),
             eh_frame_header: false,
             ..Default::default()
         },
diff --git a/compiler/rustc_target/src/spec/riscv_base.rs b/compiler/rustc_target/src/spec/riscv_base.rs
deleted file mode 100644
index 5bcbb2e621b..00000000000
--- a/compiler/rustc_target/src/spec/riscv_base.rs
+++ /dev/null
@@ -1,22 +0,0 @@
-use crate::spec::abi::Abi;
-
-// All the calling conventions trigger an assertion(Unsupported calling
-// convention) in llvm on RISCV
-pub fn unsupported_abis() -> Vec<Abi> {
-    vec![
-        Abi::Cdecl,
-        Abi::Stdcall { unwind: false },
-        Abi::Stdcall { unwind: true },
-        Abi::Fastcall,
-        Abi::Vectorcall,
-        Abi::Thiscall { unwind: false },
-        Abi::Thiscall { unwind: true },
-        Abi::Aapcs,
-        Abi::Win64,
-        Abi::SysV64,
-        Abi::PtxKernel,
-        Abi::Msp430Interrupt,
-        Abi::X86Interrupt,
-        Abi::AmdGpuKernel,
-    ]
-}
diff --git a/compiler/rustc_target/src/spec/thumb_base.rs b/compiler/rustc_target/src/spec/thumb_base.rs
index fbe4dd5b501..bac1203980e 100644
--- a/compiler/rustc_target/src/spec/thumb_base.rs
+++ b/compiler/rustc_target/src/spec/thumb_base.rs
@@ -43,7 +43,6 @@ pub fn opts() -> TargetOptions {
         // Similarly, one almost always never wants to use relocatable code because of the extra
         // costs it involves.
         relocation_model: RelocModel::Static,
-        unsupported_abis: super::arm_base::unsupported_abis(),
         // When this section is added a volatile load to its start address is also generated. This
         // volatile load is a footgun as it can end up loading an invalid memory address, depending
         // on how the user set up their linker scripts. This section adds pretty printer for stuff
diff --git a/compiler/rustc_target/src/spec/thumbv7a_pc_windows_msvc.rs b/compiler/rustc_target/src/spec/thumbv7a_pc_windows_msvc.rs
index 1232daa577f..369e6cd5e93 100644
--- a/compiler/rustc_target/src/spec/thumbv7a_pc_windows_msvc.rs
+++ b/compiler/rustc_target/src/spec/thumbv7a_pc_windows_msvc.rs
@@ -2,7 +2,6 @@ use crate::spec::{LinkerFlavor, LldFlavor, PanicStrategy, Target, TargetOptions}
 
 pub fn target() -> Target {
     let mut base = super::windows_msvc_base::opts();
-
     // Prevent error LNK2013: BRANCH24(T) fixup overflow
     // The LBR optimization tries to eliminate branch islands,
     // but if the displacement is larger than can fit
@@ -17,20 +16,17 @@ pub fn target() -> Target {
         .or_default()
         .push(pre_link_args_msvc);
 
-    // FIXME(jordanrh): use PanicStrategy::Unwind when SEH is
-    // implemented for windows/arm in LLVM
-    base.panic_strategy = PanicStrategy::Abort;
-
     Target {
         llvm_target: "thumbv7a-pc-windows-msvc".to_string(),
         pointer_width: 32,
         data_layout: "e-m:w-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
-
         options: TargetOptions {
             features: "+vfp3,+neon".to_string(),
             max_atomic_width: Some(64),
-            unsupported_abis: super::arm_base::unsupported_abis(),
+            // FIXME(jordanrh): use PanicStrategy::Unwind when SEH is
+            // implemented for windows/arm in LLVM
+            panic_strategy: PanicStrategy::Abort,
             ..base
         },
     }
diff --git a/compiler/rustc_target/src/spec/thumbv7a_uwp_windows_msvc.rs b/compiler/rustc_target/src/spec/thumbv7a_uwp_windows_msvc.rs
index e6a59f015c9..b44c0085005 100644
--- a/compiler/rustc_target/src/spec/thumbv7a_uwp_windows_msvc.rs
+++ b/compiler/rustc_target/src/spec/thumbv7a_uwp_windows_msvc.rs
@@ -1,14 +1,6 @@
 use crate::spec::{PanicStrategy, Target, TargetOptions};
 
 pub fn target() -> Target {
-    let mut base = super::windows_uwp_msvc_base::opts();
-    base.max_atomic_width = Some(64);
-    base.has_elf_tls = true;
-
-    // FIXME(jordanrh): use PanicStrategy::Unwind when SEH is
-    // implemented for windows/arm in LLVM
-    base.panic_strategy = PanicStrategy::Abort;
-
     Target {
         llvm_target: "thumbv7a-pc-windows-msvc".to_string(),
         pointer_width: 32,
@@ -16,8 +8,12 @@ pub fn target() -> Target {
         arch: "arm".to_string(),
         options: TargetOptions {
             features: "+vfp3,+neon".to_string(),
-            unsupported_abis: super::arm_base::unsupported_abis(),
-            ..base
+            max_atomic_width: Some(64),
+            has_elf_tls: true,
+            // FIXME(jordanrh): use PanicStrategy::Unwind when SEH is
+            // implemented for windows/arm in LLVM
+            panic_strategy: PanicStrategy::Abort,
+            ..super::windows_uwp_msvc_base::opts()
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/thumbv7neon_linux_androideabi.rs b/compiler/rustc_target/src/spec/thumbv7neon_linux_androideabi.rs
index 58b0a9d2202..14020b88695 100644
--- a/compiler/rustc_target/src/spec/thumbv7neon_linux_androideabi.rs
+++ b/compiler/rustc_target/src/spec/thumbv7neon_linux_androideabi.rs
@@ -10,15 +10,16 @@ use crate::spec::{LinkerFlavor, Target, TargetOptions};
 
 pub fn target() -> Target {
     let mut base = super::android_base::opts();
-    base.features = "+v7,+thumb-mode,+thumb2,+vfp3,+neon".to_string();
-    base.max_atomic_width = Some(64);
     base.pre_link_args.entry(LinkerFlavor::Gcc).or_default().push("-march=armv7-a".to_string());
-
     Target {
         llvm_target: "armv7-none-linux-android".to_string(),
         pointer_width: 32,
         data_layout: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
-        options: TargetOptions { unsupported_abis: super::arm_base::unsupported_abis(), ..base },
+        options: TargetOptions {
+            features: "+v7,+thumb-mode,+thumb2,+vfp3,+neon".to_string(),
+            max_atomic_width: Some(64),
+            ..base
+        },
     }
 }
diff --git a/compiler/rustc_target/src/spec/thumbv7neon_unknown_linux_gnueabihf.rs b/compiler/rustc_target/src/spec/thumbv7neon_unknown_linux_gnueabihf.rs
index 12d816d095b..4042d539416 100644
--- a/compiler/rustc_target/src/spec/thumbv7neon_unknown_linux_gnueabihf.rs
+++ b/compiler/rustc_target/src/spec/thumbv7neon_unknown_linux_gnueabihf.rs
@@ -7,19 +7,16 @@ use crate::spec::{Target, TargetOptions};
 // https://static.docs.arm.com/ddi0406/cd/DDI0406C_d_armv7ar_arm.pdf
 
 pub fn target() -> Target {
-    let base = super::linux_gnu_base::opts();
     Target {
         llvm_target: "armv7-unknown-linux-gnueabihf".to_string(),
         pointer_width: 32,
         data_layout: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
-
         options: TargetOptions {
             // Info about features at https://wiki.debian.org/ArmHardFloatPort
             features: "+v7,+thumb-mode,+thumb2,+vfp3,+neon".to_string(),
             max_atomic_width: Some(64),
-            unsupported_abis: super::arm_base::unsupported_abis(),
-            ..base
+            ..super::linux_gnu_base::opts()
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/thumbv7neon_unknown_linux_musleabihf.rs b/compiler/rustc_target/src/spec/thumbv7neon_unknown_linux_musleabihf.rs
index 020de87147c..318b864a9cf 100644
--- a/compiler/rustc_target/src/spec/thumbv7neon_unknown_linux_musleabihf.rs
+++ b/compiler/rustc_target/src/spec/thumbv7neon_unknown_linux_musleabihf.rs
@@ -7,7 +7,6 @@ use crate::spec::{Target, TargetOptions};
 // https://static.docs.arm.com/ddi0406/cd/DDI0406C_d_armv7ar_arm.pdf
 
 pub fn target() -> Target {
-    let base = super::linux_musl_base::opts();
     Target {
         // It's important we use "gnueabihf" and not "musleabihf" here. LLVM
         // uses it to determine the calling convention and float ABI, and LLVM
@@ -22,9 +21,8 @@ pub fn target() -> Target {
         options: TargetOptions {
             features: "+v7,+thumb-mode,+thumb2,+vfp3,+neon".to_string(),
             max_atomic_width: Some(64),
-            unsupported_abis: super::arm_base::unsupported_abis(),
             mcount: "\u{1}mcount".to_string(),
-            ..base
+            ..super::linux_musl_base::opts()
         },
     }
 }