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Diffstat (limited to 'tests/codegen/frame-pointer-cli-control.rs')
| -rw-r--r-- | tests/codegen/frame-pointer-cli-control.rs | 61 |
1 files changed, 0 insertions, 61 deletions
diff --git a/tests/codegen/frame-pointer-cli-control.rs b/tests/codegen/frame-pointer-cli-control.rs deleted file mode 100644 index a65dd132763..00000000000 --- a/tests/codegen/frame-pointer-cli-control.rs +++ /dev/null @@ -1,61 +0,0 @@ -//@ add-core-stubs -//@ compile-flags: --crate-type=rlib -Copt-level=0 -//@ revisions: force-on aarch64-apple aarch64-apple-on aarch64-apple-off -//@ [force-on] compile-flags: -Cforce-frame-pointers=on -//@ [aarch64-apple] needs-llvm-components: aarch64 -//@ [aarch64-apple] compile-flags: --target=aarch64-apple-darwin -//@ [aarch64-apple-on] needs-llvm-components: aarch64 -//@ [aarch64-apple-on] compile-flags: --target=aarch64-apple-darwin -Cforce-frame-pointers=on -//@ [aarch64-apple-off] needs-llvm-components: aarch64 -//@ [aarch64-apple-off] compile-flags: --target=aarch64-apple-darwin -Cforce-frame-pointers=off -/*! - -Tests the extent to which frame pointers can be controlled by the CLI. -The behavior of our frame pointer options, at present, is an irreversible ratchet, where -a "weaker" option that allows omitting frame pointers may be overridden by the target demanding -that all code (or all non-leaf code, more often) must be compiled with frame pointers. -This was discussed on 2025-05-22 in the T-compiler meeting and accepted as an intentional change, -ratifying the prior decisions by compiler contributors and reviewers as correct, -though it was also acknowledged that the flag allows somewhat confusing inputs. - -We find aarch64-apple-darwin useful because of its icy-clear policy regarding frame pointers, -e.g. <https://developer.apple.com/documentation/xcode/writing-arm64-code-for-apple-platforms> says: - -* The frame pointer register (x29) must always address a valid frame record. Some functions — - such as leaf functions or tail calls — may opt not to create an entry in this list. - As a result, stack traces are always meaningful, even without debug information. - -Many Rust fn, if externally visible, may be expected to follow target ABI by tools or asm code! -This can make it a problem to generate ABI-incorrect code, which may mean "with frame pointers". -For this and other reasons, `-Cforce-frame-pointers=off` cannot override the target definition. -This can cause some confusion because it is "reverse polarity" relative to C compilers, which have -commands like `-fomit-frame-pointer`, `-fomit-leaf-frame-pointer`, or `-fno-omit-frame-pointer`! - -Specific cases where platforms or tools rely on frame pointers for sound or correct unwinding: -- illumos: <https://smartos.org/bugview/OS-7515> -- aarch64-windows: <https://github.com/rust-lang/rust/issues/123686> -- aarch64-linux: <https://github.com/rust-lang/rust/issues/123733> -- dtrace (freebsd and openbsd): <https://github.com/rust-lang/rust/issues/97723> -- openbsd: <https://github.com/rust-lang/rust/issues/43575> -- i686-msvc <https://github.com/rust-lang/backtrace-rs/pull/584#issuecomment-1966177530> -- i686-mingw: <https://github.com/rust-lang/rust/commit/3f1d3948d6d434b34dd47f132c126a6cb6b8a4ab> -*/ -#![feature(no_core, lang_items)] -#![no_core] - -extern crate minicore; - -// CHECK: i32 @peach{{.*}}[[PEACH_ATTRS:\#[0-9]+]] { -#[no_mangle] -pub fn peach(x: u32) -> u32 { - x -} - -// CHECK: attributes [[PEACH_ATTRS]] = { -// force-on-SAME: {{.*}}"frame-pointer"="all" -// aarch64-apple-SAME: {{.*}}"frame-pointer"="non-leaf" -// aarch64-apple-on-SAME: {{.*}}"frame-pointer"="all" -// -// yes, we are testing this doesn't do anything: -// aarch64-apple-off-SAME: {{.*}}"frame-pointer"="non-leaf" -// CHECK-SAME: } |