Auto merge of #146317 - saethlin:panic=immediate-abort, r=nnethercote

Add panic=immediate-abort

MCP: https://github.com/rust-lang/compiler-team/issues/909

This adds a new panic strategy, `-Cpanic=immediate-abort`. This panic strategy essentially just codifies use of `-Zbuild-std-features=panic_immediate_abort`. This PR is intended to just set up infrastructure, and while it will change how the compiler is invoked for users of the feature, there should be no other impacts.

In many parts of the compiler, `PanicStrategy::ImmediateAbort` behaves just like `PanicStrategy::Abort`, because actually most parts of the compiler just mean to ask "can this unwind?" so I've added a helper function so we can say `sess.panic_strategy().unwinds()`.

The panic and unwind strategies have some level of compatibility, which mostly means that we can pre-compile the sysroot with unwinding panics then the sysroot can be linked with aborting panics later. The immediate-abort strategy is all-or-nothing, enforced by `compiler/rustc_metadata/src/dependency_format.rs` and this is tested for in `tests/ui/panic-runtime/`. We could _technically_ be more compatible with the other panic strategies, but immediately-aborting panics primarily exist for users who want to eliminate all the code size responsible for the panic runtime. I'm open to other use cases if people want to present them, but not right now. This PR is already large.

`-Cpanic=immediate-abort` sets both `cfg(panic = "immediate-abort")` _and_ `cfg(panic = "abort")`. bjorn3 pointed out that people may be checking for the abort cfg to ask if panics will unwind, and also the sysroot feature this is replacing used to require `-Cpanic=abort` so this seems like a good back-compat step. At least for the moment. Unclear if this is a good idea indefinitely. I can imagine this being confusing.

The changes to the standard library attributes are purely mechanical. Apart from that, I removed an `unsafe` we haven't needed for a while since the `abort` intrinsic became safe, and I've added a helpful diagnostic for people trying to use the old feature.

To test that `-Cpanic=immediate-abort` conflicts with other panic strategies, I've beefed up the core-stubs infrastructure a bit. There is now a separate attribute to set flags on it.

I've added a test that this produces the desired codegen, called `tests/run-make-cargo/panic-immediate-abort-codegen/` and also a separate run-make-cargo test that checks that we can build a binary.

28 files changed, 320 insertions, 9 deletions

diff --git a/tests/run-make-cargo/panic-immediate-abort-codegen/Cargo.toml b/tests/run-make-cargo/panic-immediate-abort-codegen/Cargo.toml
new file mode 100644
index 00000000000..3c61c12a84e
--- /dev/null
+++ b/tests/run-make-cargo/panic-immediate-abort-codegen/Cargo.toml
@@ -0,0 +1,12 @@
+cargo-features = ["profile-rustflags"]
+
+[package]
+name = "panic_scenarios"
+version = "0.1.0"
+edition = "2024"
+
+[lib]
+path = "lib.rs"
+
+[profile.release]
+rustflags = ["-Zmerge-functions=disabled", "-Zcodegen-source-order", "--emit=llvm-ir"]
diff --git a/tests/run-make-cargo/panic-immediate-abort-codegen/lib.rs b/tests/run-make-cargo/panic-immediate-abort-codegen/lib.rs
new file mode 100644
index 00000000000..1e20da93ba8
--- /dev/null
+++ b/tests/run-make-cargo/panic-immediate-abort-codegen/lib.rs
@@ -0,0 +1,65 @@
+#![no_std]
+
+#[unsafe(no_mangle)]
+pub fn panic_noarg() {
+    // CHECK-LABEL: @panic_noarg(
+    // CHECK-NEXT: start:
+    // CHECK-NEXT: tail call void @llvm.trap()
+    panic!();
+}
+
+#[unsafe(no_mangle)]
+pub fn panic_str() {
+    // CHECK-LABEL: @panic_str(
+    // CHECK-NEXT: start:
+    // CHECK-NEXT: tail call void @llvm.trap()
+    panic!("ouch");
+}
+
+#[unsafe(no_mangle)]
+pub fn bounds_check(x: &[u8], idx: usize) -> &u8 {
+    // CHECK-LABEL: @bounds_check(
+    // CHECK-NEXT: start:
+    // CHECK-NEXT: icmp ult
+    // CHECK-NEXT: br i1
+    // CHECK: bb1:
+    // CHECK-NEXT: getelementptr inbounds nuw i8
+    // CHECK-NEXT: ret ptr
+    // CHECK: panic:
+    // CHECK-NEXT: tail call void @llvm.trap()
+    &x[idx]
+}
+
+#[unsafe(no_mangle)]
+pub fn str_bounds_check(x: &str, idx: usize) -> &str {
+    // CHECK-LABEL: @str_bounds_check(
+    // CHECK-NOT: call
+    // CHECK: tail call void @llvm.trap()
+    // CHECK-NOT: call
+    &x[idx..]
+}
+
+#[unsafe(no_mangle)]
+pub fn unsigned_integer_div(x: u16, y: u16) -> u16 {
+    // CHECK-LABEL: @unsigned_integer_div(
+    // CHECK-NEXT: start:
+    // CHECK-NEXT: icmp eq i16
+    // CHECK-NEXT: br i1
+    // CHECK: bb1:
+    // CHECK-NEXT: udiv i16
+    // CHECK-NEXT: ret i16
+    // CHECK: panic:
+    // CHECK-NEXT: tail call void @llvm.trap()
+    x / y
+}
+
+#[unsafe(no_mangle)]
+pub fn refcell_already_borrowed() {
+    // CHECK-LABEL: @refcell_already_borrowed(
+    // CHECK-NOT: call
+    // CHECK: tail call void @llvm.trap()
+    // CHECK-NOT: call
+    let r = core::cell::RefCell::new(0u8);
+    let _guard = r.borrow_mut();
+    r.borrow_mut();
+}
diff --git a/tests/run-make-cargo/panic-immediate-abort-codegen/rmake.rs b/tests/run-make-cargo/panic-immediate-abort-codegen/rmake.rs
new file mode 100644
index 00000000000..d7a7a8bfd8c
--- /dev/null
+++ b/tests/run-make-cargo/panic-immediate-abort-codegen/rmake.rs
@@ -0,0 +1,46 @@
+// This is a codegen test which checks that when code is compiled with panic=immediate-abort,
+// we get a `tail call void @llvm.trap()` in user code instead of a call into the standard
+// library's panic formatting code (such as panic_fmt) or one of the numerous panic outlining shims
+// (such as slice_index_fail).
+
+#![deny(warnings)]
+
+use run_make_support::{cargo, llvm_filecheck, path, rfs, target};
+
+fn main() {
+    let target_dir = path("target");
+
+    cargo()
+        .args(&[
+            "build",
+            "--release",
+            "--lib",
+            "--manifest-path",
+            "Cargo.toml",
+            "-Zbuild-std=core",
+            "--target",
+            &target(),
+        ])
+        .env("RUSTFLAGS", "-Zunstable-options -Cpanic=immediate-abort")
+        .env("CARGO_TARGET_DIR", &target_dir)
+        .env("RUSTC_BOOTSTRAP", "1")
+        // Visual Studio 2022 requires that the LIB env var be set so it can
+        // find the Windows SDK.
+        .env("LIB", std::env::var("LIB").unwrap_or_default())
+        .run();
+
+    let out_dir = target_dir.join(target()).join("release").join("deps");
+    let ir_file = rfs::read_dir(out_dir)
+        .find_map(|e| {
+            let path = e.unwrap().path();
+            let file_name = path.file_name().unwrap().to_str().unwrap();
+            if file_name.starts_with("panic_scenarios") && file_name.ends_with(".ll") {
+                Some(path)
+            } else {
+                None
+            }
+        })
+        .unwrap();
+
+    llvm_filecheck().patterns("lib.rs").input_file(ir_file).run();
+}
diff --git a/tests/run-make-cargo/panic-immediate-abort-works/hello/Cargo.toml b/tests/run-make-cargo/panic-immediate-abort-works/hello/Cargo.toml
new file mode 100644
index 00000000000..1e278d557c0
--- /dev/null
+++ b/tests/run-make-cargo/panic-immediate-abort-works/hello/Cargo.toml
@@ -0,0 +1,4 @@
+[package]
+name = "hello"
+version = "0.1.0"
+edition = "2024"
diff --git a/tests/run-make-cargo/panic-immediate-abort-works/hello/src/main.rs b/tests/run-make-cargo/panic-immediate-abort-works/hello/src/main.rs
new file mode 100644
index 00000000000..f328e4d9d04
--- /dev/null
+++ b/tests/run-make-cargo/panic-immediate-abort-works/hello/src/main.rs
@@ -0,0 +1 @@
+fn main() {}
diff --git a/tests/run-make-cargo/panic-immediate-abort-works/rmake.rs b/tests/run-make-cargo/panic-immediate-abort-works/rmake.rs
new file mode 100644
index 00000000000..3eeef38c962
--- /dev/null
+++ b/tests/run-make-cargo/panic-immediate-abort-works/rmake.rs
@@ -0,0 +1,39 @@
+// This test ensures we are able to compile and link a simple binary with panic=immediate-abort.
+// The test panic-immediate-abort-codegen checks that panic strategy produces the desired codegen,
+// but is based on compiling a library crate (which is the norm for codegen tests because it is
+// cleaner and more portable). So this test ensures that we didn't mix up a cfg or a compiler
+// implementation detail in a way that makes panic=immediate-abort encounter errors at link time.
+
+// Ideally this test would be run for most targets, but unfortunately:
+// This test is currently written using `fn main() {}` which requires std.
+// And since the default linker is only a linker for the host, we can't handle cross-compilation.
+// Both of these shortcomings could be addressed at the cost of making the test more complicated.
+//@ needs-target-std
+//@ ignore-cross-compile
+
+#![deny(warnings)]
+
+use run_make_support::{cargo, path, target};
+
+fn main() {
+    let target_dir = path("target");
+
+    cargo()
+        .current_dir("hello")
+        .args(&[
+            "build",
+            "--release",
+            "--manifest-path",
+            "Cargo.toml",
+            "-Zbuild-std",
+            "--target",
+            &target(),
+        ])
+        .env("RUSTFLAGS", "-Zunstable-options -Cpanic=immediate-abort")
+        .env("CARGO_TARGET_DIR", &target_dir)
+        .env("RUSTC_BOOTSTRAP", "1")
+        // Visual Studio 2022 requires that the LIB env var be set so it can
+        // find the Windows SDK.
+        .env("LIB", std::env::var("LIB").unwrap_or_default())
+        .run();
+}
diff --git a/tests/ui/check-cfg/report-in-external-macros.cargo.stderr b/tests/ui/check-cfg/report-in-external-macros.cargo.stderr
index 989a01f2244..4b5fc91c7eb 100644
--- a/tests/ui/check-cfg/report-in-external-macros.cargo.stderr
+++ b/tests/ui/check-cfg/report-in-external-macros.cargo.stderr
@@ -18,7 +18,7 @@ warning: unexpected `cfg` condition value: `UNEXPECTED_VALUE`
 LL |     cfg_macro::my_lib_macro_value!();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = note: expected values for `panic` are: `abort` and `unwind`
+   = note: expected values for `panic` are: `abort`, `immediate-abort`, and `unwind`
    = note: using a cfg inside a macro will use the cfgs from the destination crate and not the ones from the defining crate
    = help: try referring to `cfg_macro::my_lib_macro_value` crate for guidance on how handle this unexpected cfg
    = help: the macro `cfg_macro::my_lib_macro_value` may come from an old version of the `cfg_macro` crate, try updating your dependency with `cargo update -p cfg_macro`
diff --git a/tests/ui/check-cfg/report-in-external-macros.rustc.stderr b/tests/ui/check-cfg/report-in-external-macros.rustc.stderr
index 95d10e014f3..0d99d061d28 100644
--- a/tests/ui/check-cfg/report-in-external-macros.rustc.stderr
+++ b/tests/ui/check-cfg/report-in-external-macros.rustc.stderr
@@ -18,7 +18,7 @@ warning: unexpected `cfg` condition value: `UNEXPECTED_VALUE`
 LL |     cfg_macro::my_lib_macro_value!();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = note: expected values for `panic` are: `abort` and `unwind`
+   = note: expected values for `panic` are: `abort`, `immediate-abort`, and `unwind`
    = note: using a cfg inside a macro will use the cfgs from the destination crate and not the ones from the defining crate
    = help: try referring to `cfg_macro::my_lib_macro_value` crate for guidance on how handle this unexpected cfg
    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more information about checking conditional configuration
diff --git a/tests/ui/check-cfg/well-known-values.stderr b/tests/ui/check-cfg/well-known-values.stderr
index df2357696a3..e62f741b302 100644
--- a/tests/ui/check-cfg/well-known-values.stderr
+++ b/tests/ui/check-cfg/well-known-values.stderr
@@ -80,7 +80,7 @@ warning: unexpected `cfg` condition value: `_UNEXPECTED_VALUE`
 LL |     panic = "_UNEXPECTED_VALUE",
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = note: expected values for `panic` are: `abort` and `unwind`
+   = note: expected values for `panic` are: `abort`, `immediate-abort`, and `unwind`
    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more information about checking conditional configuration
 
 warning: unexpected `cfg` condition value: `_UNEXPECTED_VALUE`
diff --git a/tests/ui/panic-runtime/auxiliary/needs-abort.rs b/tests/ui/panic-runtime/auxiliary/needs-abort.rs
index 21f862e4b43..cba4907dbb6 100644
--- a/tests/ui/panic-runtime/auxiliary/needs-abort.rs
+++ b/tests/ui/panic-runtime/auxiliary/needs-abort.rs
@@ -1,5 +1,7 @@
 //@ compile-flags:-C panic=abort
 //@ no-prefer-dynamic
 
+#![feature(no_core)]
 #![crate_type = "rlib"]
 #![no_std]
+#![no_core]
diff --git a/tests/ui/panic-runtime/auxiliary/needs-immediate-abort.rs b/tests/ui/panic-runtime/auxiliary/needs-immediate-abort.rs
new file mode 100644
index 00000000000..4a41d16faa0
--- /dev/null
+++ b/tests/ui/panic-runtime/auxiliary/needs-immediate-abort.rs
@@ -0,0 +1,7 @@
+//@ compile-flags:-C panic=immediate-abort -Zunstable-options
+//@ no-prefer-dynamic
+
+#![feature(no_core)]
+#![crate_type = "rlib"]
+#![no_std]
+#![no_core]
diff --git a/tests/ui/panic-runtime/auxiliary/needs-unwind-immediate-abort.rs b/tests/ui/panic-runtime/auxiliary/needs-unwind-immediate-abort.rs
new file mode 100644
index 00000000000..295876fec52
--- /dev/null
+++ b/tests/ui/panic-runtime/auxiliary/needs-unwind-immediate-abort.rs
@@ -0,0 +1,18 @@
+//@ compile-flags:-C panic=unwind
+//@ no-prefer-dynamic
+//@ add-core-stubs
+
+#![crate_type = "rlib"]
+#![feature(no_core)]
+#![no_std]
+#![no_core]
+
+extern crate minicore;
+
+extern "C-unwind" fn foo() {}
+
+#[inline]
+fn bar() {
+    let ptr: extern "C-unwind" fn() = foo;
+    ptr();
+}
diff --git a/tests/ui/panic-runtime/bad-panic-flag1.rs b/tests/ui/panic-runtime/bad-panic-flag1.rs
index 117935847cb..575e30f785c 100644
--- a/tests/ui/panic-runtime/bad-panic-flag1.rs
+++ b/tests/ui/panic-runtime/bad-panic-flag1.rs
@@ -2,4 +2,4 @@
 
 fn main() {}
 
-//~? ERROR incorrect value `foo` for codegen option `panic` - either `unwind` or `abort` was expected
+//~? ERROR incorrect value `foo` for codegen option `panic` - either `unwind`, `abort`, or `immediate-abort` was expected
diff --git a/tests/ui/panic-runtime/bad-panic-flag1.stderr b/tests/ui/panic-runtime/bad-panic-flag1.stderr
index 013373c6f93..c30598bba53 100644
--- a/tests/ui/panic-runtime/bad-panic-flag1.stderr
+++ b/tests/ui/panic-runtime/bad-panic-flag1.stderr
@@ -1,2 +1,2 @@
-error: incorrect value `foo` for codegen option `panic` - either `unwind` or `abort` was expected
+error: incorrect value `foo` for codegen option `panic` - either `unwind`, `abort`, or `immediate-abort` was expected
 
diff --git a/tests/ui/panic-runtime/bad-panic-flag2.rs b/tests/ui/panic-runtime/bad-panic-flag2.rs
index b5d0442a033..4e34da217d7 100644
--- a/tests/ui/panic-runtime/bad-panic-flag2.rs
+++ b/tests/ui/panic-runtime/bad-panic-flag2.rs
@@ -2,4 +2,4 @@
 
 fn main() {}
 
-//~? ERROR codegen option `panic` requires either `unwind` or `abort`
+//~? ERROR codegen option `panic` requires either `unwind`, `abort`, or `immediate-abort`
diff --git a/tests/ui/panic-runtime/bad-panic-flag2.stderr b/tests/ui/panic-runtime/bad-panic-flag2.stderr
index 6ab94ea704d..c8d12749c5d 100644
--- a/tests/ui/panic-runtime/bad-panic-flag2.stderr
+++ b/tests/ui/panic-runtime/bad-panic-flag2.stderr
@@ -1,2 +1,2 @@
-error: codegen option `panic` requires either `unwind` or `abort` (C panic=<value>)
+error: codegen option `panic` requires either `unwind`, `abort`, or `immediate-abort` (C panic=<value>)
 
diff --git a/tests/ui/panic-runtime/immediate-abort-default-sysroot.rs b/tests/ui/panic-runtime/immediate-abort-default-sysroot.rs
new file mode 100644
index 00000000000..94dc7c5671e
--- /dev/null
+++ b/tests/ui/panic-runtime/immediate-abort-default-sysroot.rs
@@ -0,0 +1,15 @@
+//@ build-fail
+//@ aux-build:needs-unwind.rs
+//@ compile-flags:-C panic=immediate-abort -Zunstable-options
+//@ no-prefer-dynamic
+
+extern crate needs_unwind;
+
+// immediate-abort does not require any panic runtime, so trying to build a binary crate with
+// panic=immediate-abort and the precompiled sysroot will fail to link, because no panic runtime
+// provides the panic entrypoints used by sysroot crates.
+// This test ensures that we get a clean compile error instead of a linker error.
+
+fn main() {}
+
+//~? ERROR the crate `core` was compiled with a panic strategy which is incompatible with `immediate-abort`
diff --git a/tests/ui/panic-runtime/immediate-abort-default-sysroot.stderr b/tests/ui/panic-runtime/immediate-abort-default-sysroot.stderr
new file mode 100644
index 00000000000..bd6bdd8b667
--- /dev/null
+++ b/tests/ui/panic-runtime/immediate-abort-default-sysroot.stderr
@@ -0,0 +1,4 @@
+error: the crate `core` was compiled with a panic strategy which is incompatible with `immediate-abort`
+
+error: aborting due to 1 previous error
+
diff --git a/tests/ui/panic-runtime/need-abort-got-immediate-abort.rs b/tests/ui/panic-runtime/need-abort-got-immediate-abort.rs
new file mode 100644
index 00000000000..78977c60be9
--- /dev/null
+++ b/tests/ui/panic-runtime/need-abort-got-immediate-abort.rs
@@ -0,0 +1,21 @@
+//@ build-fail
+//@ aux-build:needs-abort.rs
+//@ compile-flags:-Cpanic=immediate-abort -Zunstable-options
+//@ no-prefer-dynamic
+//@ add-core-stubs
+//@ core-stubs-compile-flags: -Cpanic=immediate-abort -Zunstable-options
+
+#![feature(no_core)]
+#![no_std]
+#![no_main]
+#![no_core]
+
+extern crate minicore;
+extern crate needs_abort;
+
+#[no_mangle]
+extern "C" fn main(_argc: i32, _argv: *const *const u8) -> i32 {
+    0
+}
+
+//~? ERROR the crate `needs_abort` was compiled with a panic strategy which is incompatible with `immediate-abort`
diff --git a/tests/ui/panic-runtime/need-abort-got-immediate-abort.stderr b/tests/ui/panic-runtime/need-abort-got-immediate-abort.stderr
new file mode 100644
index 00000000000..65a26b676b9
--- /dev/null
+++ b/tests/ui/panic-runtime/need-abort-got-immediate-abort.stderr
@@ -0,0 +1,4 @@
+error: the crate `needs_abort` was compiled with a panic strategy which is incompatible with `immediate-abort`
+
+error: aborting due to 1 previous error
+
diff --git a/tests/ui/panic-runtime/need-immediate-abort-got-abort.rs b/tests/ui/panic-runtime/need-immediate-abort-got-abort.rs
new file mode 100644
index 00000000000..1c5f597a3f9
--- /dev/null
+++ b/tests/ui/panic-runtime/need-immediate-abort-got-abort.rs
@@ -0,0 +1,20 @@
+//@ build-fail
+//@ aux-build:needs-immediate-abort.rs
+//@ compile-flags:-C panic=abort
+//@ no-prefer-dynamic
+//@ add-core-stubs
+//@ core-stubs-compile-flags: -Zunstable-options -Cpanic=immediate-abort
+
+#![feature(no_core)]
+#![no_std]
+#![no_main]
+#![no_core]
+
+extern crate minicore;
+extern crate needs_immediate_abort;
+
+extern "C" fn main(argc: i32, argv: *const *const u8) -> i32 {
+    0
+}
+
+//~? ERROR the crate `need_immediate_abort_got_abort` was compiled with a panic strategy which is incompatible with `immediate-abort`
diff --git a/tests/ui/panic-runtime/need-immediate-abort-got-abort.stderr b/tests/ui/panic-runtime/need-immediate-abort-got-abort.stderr
new file mode 100644
index 00000000000..8dcf120cb9f
--- /dev/null
+++ b/tests/ui/panic-runtime/need-immediate-abort-got-abort.stderr
@@ -0,0 +1,4 @@
+error: the crate `need_immediate_abort_got_abort` was compiled with a panic strategy which is incompatible with `immediate-abort`
+
+error: aborting due to 1 previous error
+
diff --git a/tests/ui/panic-runtime/need-immediate-abort-got-unwind.rs b/tests/ui/panic-runtime/need-immediate-abort-got-unwind.rs
new file mode 100644
index 00000000000..24d521230d4
--- /dev/null
+++ b/tests/ui/panic-runtime/need-immediate-abort-got-unwind.rs
@@ -0,0 +1,20 @@
+//@ build-fail
+//@ needs-unwind
+//@ aux-build:needs-immediate-abort.rs
+//@ no-prefer-dynamic
+//@ add-core-stubs
+//@ core-stubs-compile-flags: -Zunstable-options -Cpanic=immediate-abort
+
+#![feature(no_core)]
+#![no_std]
+#![no_main]
+#![no_core]
+
+extern crate minicore;
+extern crate needs_immediate_abort;
+
+extern "C" fn main(argc: i32, argv: *const *const u8) -> i32 {
+    0
+}
+
+//~? ERROR the crate `need_immediate_abort_got_unwind` was compiled with a panic strategy which is incompatible with `immediate-abort`
diff --git a/tests/ui/panic-runtime/need-immediate-abort-got-unwind.stderr b/tests/ui/panic-runtime/need-immediate-abort-got-unwind.stderr
new file mode 100644
index 00000000000..740fc80a77d
--- /dev/null
+++ b/tests/ui/panic-runtime/need-immediate-abort-got-unwind.stderr
@@ -0,0 +1,4 @@
+error: the crate `need_immediate_abort_got_unwind` was compiled with a panic strategy which is incompatible with `immediate-abort`
+
+error: aborting due to 1 previous error
+
diff --git a/tests/ui/panic-runtime/need-unwind-got-immediate-abort.rs b/tests/ui/panic-runtime/need-unwind-got-immediate-abort.rs
new file mode 100644
index 00000000000..5aec028a46c
--- /dev/null
+++ b/tests/ui/panic-runtime/need-unwind-got-immediate-abort.rs
@@ -0,0 +1,21 @@
+//@ build-fail
+//@ aux-build:needs-unwind-immediate-abort.rs
+//@ compile-flags:-C panic=immediate-abort -Zunstable-options
+//@ no-prefer-dynamic
+//@ add-core-stubs
+//@ core-stubs-compile-flags: -Zunstable-options -Cpanic=immediate-abort
+
+#![feature(no_core)]
+#![no_std]
+#![no_main]
+#![no_core]
+
+extern crate minicore;
+extern crate needs_unwind_immediate_abort;
+
+#[no_mangle]
+extern "C" fn main(_argc: i32, _argv: *const *const u8) -> i32 {
+    0
+}
+
+//~? ERROR the crate `needs_unwind_immediate_abort` was compiled with a panic strategy which is incompatible with `immediate-abort`
diff --git a/tests/ui/panic-runtime/need-unwind-got-immediate-abort.stderr b/tests/ui/panic-runtime/need-unwind-got-immediate-abort.stderr
new file mode 100644
index 00000000000..8b3747d644f
--- /dev/null
+++ b/tests/ui/panic-runtime/need-unwind-got-immediate-abort.stderr
@@ -0,0 +1,4 @@
+error: the crate `needs_unwind_immediate_abort` was compiled with a panic strategy which is incompatible with `immediate-abort`
+
+error: aborting due to 1 previous error
+
diff --git a/tests/ui/proc-macro/panic-abort.rs b/tests/ui/proc-macro/panic-abort.rs
index 58e1d006433..adedba4ebca 100644
--- a/tests/ui/proc-macro/panic-abort.rs
+++ b/tests/ui/proc-macro/panic-abort.rs
@@ -2,4 +2,4 @@
 //@ force-host
 //@ check-pass
 
-//~? WARN building proc macro crate with `panic=abort` may crash the compiler should the proc-macro panic
+//~? WARN building proc macro crate with `panic=abort` or `panic=immediate-abort` may crash the compiler should the proc-macro panic
diff --git a/tests/ui/proc-macro/panic-abort.stderr b/tests/ui/proc-macro/panic-abort.stderr
index a6e18614f8f..3dd75768bc4 100644
--- a/tests/ui/proc-macro/panic-abort.stderr
+++ b/tests/ui/proc-macro/panic-abort.stderr
@@ -1,4 +1,4 @@
-warning: building proc macro crate with `panic=abort` may crash the compiler should the proc-macro panic
+warning: building proc macro crate with `panic=abort` or `panic=immediate-abort` may crash the compiler should the proc-macro panic
 
 warning: 1 warning emitted