Broken LIT tests on Sanitizer Builds

I recently built with -DLLVM_USE_SANITIZER=Address, ran the LIT tests, and noticed we have at least two tests with memory bugs on main. Here are the commands I ran

$ ninja check-llvm

==2157126==ERROR: AddressSanitizer: global-buffer-overflow on address 0x7fb9f778c55f at pc 0x7fba0487419d bp 0x7ffe92a0a230 sp 0x7ffe92a099d8
READ of size 1 at 0x7fb9f778c55f thread T0
#0 0x7fba0487419c (/lib64/
#1 0x7fb9e7bcc439 in llvm::StringRef::strLen(char const*) /home/ellishoag/local/repos/llvm-project/llvm/include/llvm/ADT/StringRef.h:86
#2 0x7fb9e7bcc439 in llvm::StringRef::StringRef(char const*) /home/ellishoag/local/repos/llvm-project/llvm/include/llvm/ADT/StringRef.h:108
#3 0x7fb9e7bcc439 in getMnemonic /home/ellishoag/local/repos/llvm-project/llvm/lib/MC/MCAsmStreamer.cpp:159

Failed Tests (2):
LLVM :: CodeGen/AArch64/machine-outliner-remarks.ll
LLVM :: CodeGen/X86/x86-shrink-wrapping.ll

I think check-clang also has some broken tests. Should we be running these checks in ? I’m not super familiar with this site, but it seems that we have asan builds, but that we don’t run check-llvm or check-clang.

Hi Ellis,

Are you building using GCC as the host compiler? I can’t say that building clang with gcc-ASan is a well tested (or well-supported) configuration.

We do have ASan buildbots that run check-all, but the host compiler is clang:


This one runs with Asan and does check-llvm
However we don’t set -DBUILD_SHARED_LIBS=On

Yeah it seems I was using gcc so I can try again with clang. Thanks!