For https://chromium-review.googlesource.com/c/chromium/src/+/6038168 it fails across all platforms, e.g. https://ci.chromium.org/ui/p/chromium/builders/try/linux_upload_rust/2608/overview
 ---- [codegen] tests/codegen/aarch64-softfloat.rs stdout ----
 
 error: verification with 'FileCheck' failed
 status: exit status: 1
 command: "/b/s/w/ir/cache/builder/src/third_party/rust-toolchain-intermediate/llvm-host-install/bin/FileCheck" "--input-file" "/b/s/w/ir/cache/builder/src/third_party/rust-src/build/x86_64-unknown-linux-gnu/test/codegen/aarch64-softfloat/aarch64-softfloat.ll" "/b/s/w/ir/cache/builder/src/third_party/rust-src/tests/codegen/aarch64-softfloat.rs" "--check-prefix=CHECK" "--check-prefix" "NONMSVC" "--allow-unused-prefixes" "--dump-input-context" "100"
 stdout: none
 --- stderr -------------------------------
 /b/s/w/ir/cache/builder/src/third_party/rust-src/tests/codegen/aarch64-softfloat.rs:44:11: error: CHECK: expected string not found in input
 // CHECK: void @pass_f64_pair_Rust(ptr {{[^,]*}}, ptr {{[^,]*}})
           ^
 /b/s/w/ir/cache/builder/src/third_party/rust-src/build/x86_64-unknown-linux-gnu/test/codegen/aarch64-softfloat/aarch64-softfloat.ll:31:58: note: scanning from here
 define dso_local i64 @pass_f32_pair_Rust(i64 returned %0) unnamed_addr #0 {
                                                          ^
 /b/s/w/ir/cache/builder/src/third_party/rust-src/build/x86_64-unknown-linux-gnu/test/codegen/aarch64-softfloat/aarch64-softfloat.ll:37:18: note: possible intended match here
 define dso_local void @pass_f64_pair_Rust(ptr dead_on_unwind noalias nocapture noundef writable writeonly sret([16 x i8]) align 8 dereferenceable(16) initializes((0, 16)) %_0, ptr noalias nocapture noundef readonly align 8 dereferenceable(16) %x) unnamed_addr #1 {
                  ^
 
 Input file: /b/s/w/ir/cache/builder/src/third_party/rust-src/build/x86_64-unknown-linux-gnu/test/codegen/aarch64-softfloat/aarch64-softfloat.ll
 Check file: /b/s/w/ir/cache/builder/src/third_party/rust-src/tests/codegen/aarch64-softfloat.rs
 
 -dump-input=help explains the following input dump.
 
 Input was:
 <<<<<<
             1: ; ModuleID = 'aarch64_softfloat.54093907c74d9ec4-cgu.0' 
             2: source_filename = "aarch64_softfloat.54093907c74d9ec4-cgu.0" 
             3: target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128-Fn32" 
             4: target triple = "aarch64-unknown-none" 
             5:  
             6: ; Function Attrs: mustprogress nofree norecurse noredzone nosync nounwind willreturn memory(none) 
             7: define dso_local i64 @pass_f64_C(i64 returned %0) unnamed_addr #0 { 
             8: start: 
             9:  ret i64 %0 
            10: } 
            11:  
            12: ; Function Attrs: mustprogress nofree norecurse noredzone nosync nounwind willreturn memory(none) 
            13: define dso_local i64 @pass_f32_pair_C(i64 returned %0) unnamed_addr #0 { 
            14: start: 
            15:  ret i64 %0 
            16: } 
            17:  
            18: ; Function Attrs: mustprogress nofree norecurse noredzone nosync nounwind willreturn memory(none) 
            19: define dso_local [2 x i64] @pass_f64_pair_C([2 x i64] returned %0) unnamed_addr #0 { 
            20: start: 
            21:  ret [2 x i64] %0 
            22: } 
            23:  
            24: ; Function Attrs: mustprogress nofree norecurse noredzone nosync nounwind willreturn memory(none) 
            25: define dso_local i64 @pass_f64_Rust(i64 returned %0) unnamed_addr #0 { 
            26: start: 
            27:  ret i64 %0 
            28: } 
            29:  
            30: ; Function Attrs: mustprogress nofree norecurse noredzone nosync nounwind willreturn memory(none) 
            31: define dso_local i64 @pass_f32_pair_Rust(i64 returned %0) unnamed_addr #0 { 
 check:44'0                                                              X~~~~~~~~~~~~~~~~~~ error: no match found
            32: start: 
 check:44'0     ~~~~~~~
            33:  ret i64 %0 
 check:44'0     ~~~~~~~~~~~~
            34: } 
 check:44'0     ~~
            35:  
 check:44'0     ~
            36: ; Function Attrs: mustprogress nofree norecurse noredzone nosync nounwind willreturn memory(argmem: readwrite) 
 check:44'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
            37: define dso_local void @pass_f64_pair_Rust(ptr dead_on_unwind noalias nocapture noundef writable writeonly sret([16 x i8]) align 8 dereferenceable(16) initializes((0, 16)) %_0, ptr noalias nocapture noundef readonly align 8 dereferenceable(16) %x) unnamed_addr #1 { 
 check:44'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 check:44'1                      ?                                                                                                                                                                                                                                                        possible intended match
            38: start: 
 check:44'0     ~~~~~~~
            39:  %0 = load double, ptr %x, align 8, !noundef !1 
 check:44'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
            40:  %1 = getelementptr inbounds i8, ptr %x, i64 8 
 check:44'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
            41:  %2 = load double, ptr %1, align 8, !noundef !1 
 check:44'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
            42:  store double %0, ptr %_0, align 8 
 check:44'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
            43:  %3 = getelementptr inbounds i8, ptr %_0, i64 8 
 check:44'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
            44:  store double %2, ptr %3, align 8 
 check:44'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
            45:  ret void 
 check:44'0     ~~~~~~~~~~
            46: } 
 check:44'0     ~~
            47:  
 check:44'0     ~
            48: attributes #0 = { mustprogress nofree norecurse noredzone nosync nounwind willreturn memory(none) "probe-stack"="inline-asm" "target-cpu"="generic" "target-features"="+v8a,+strict-align,-neon,-fp-armv8" } 
 check:44'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
            49: attributes #1 = { mustprogress nofree norecurse noredzone nosync nounwind willreturn memory(argmem: readwrite) "probe-stack"="inline-asm" "target-cpu"="generic" "target-features"="+v8a,+strict-align,-neon,-fp-armv8" } 
 check:44'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
            50:  
 check:44'0     ~
            51: !llvm.ident = !{!0} 
 check:44'0     ~~~~~~~~~~~~~~~~~~~~
            52:  
 check:44'0     ~
            53: !0 = !{!"rustc version 1.85.0-dev (28fc2ba7142654fa6e654926f96ff913027b200e-1-llvmorg-20-init-13308-gff7b42c1 chromium)"} 
 check:44'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
            54: !1 = !{} 
 check:44'0     ~~~~~~~~~
 >>>>>>
 ------------------------------------------
 
 
 
 failures:
     [codegen] tests/codegen/aarch64-softfloat.rs