https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113341
--- Comment #13 from John Paul Adrian Glaubitz <glaubitz at physik dot
fu-berlin.de> ---
(In reply to Andrew Pinski from comment #7)
> `-fno-lifetime-dse` is already used but I get the feeling there might be
> strict aliasing issues in the code though. What happens if you add
> -fno-strict-aliasing ?
>
> This code gives me strict aliasing violation vibes:
> ```
> T **getAddressOfPointer(ExternalASTSource *Source) const {
> // Ensure the integer is in pointer form.
> (void)get(Source);
> return reinterpret_cast<T**>(&Ptr);
> }
> ```
I tried with the following diff but that did not fix the issue:
diff --git a/llvm/cmake/modules/HandleLLVMOptions.cmake
b/llvm/cmake/modules/HandleLLVMOptions.cmake
index 5ca580fbb59c..51c470dcc3ed 100644
--- a/llvm/cmake/modules/HandleLLVMOptions.cmake
+++ b/llvm/cmake/modules/HandleLLVMOptions.cmake
@@ -679,7 +679,7 @@ if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
# crash if LLVM is built with GCC and LTO enabled (#57740). Until
# these bugs are fixed, we need to disable dead store eliminations
# based on object lifetime.
- append("-fno-lifetime-dse" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
+ append("-fno-lifetime-dse -fno-strict-aliasing" CMAKE_C_FLAGS
CMAKE_CXX_FLAGS)
endif ()
# Modules enablement for GCC-compatible compilers:
