https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68601
--- Comment #2 from Keno Fischer <kfischer at college dot harvard.edu> --- The default options used by LLVM's build system: ``` g++ -m64 -I/home/Administrator/julia/deps/build/llvm-svn/build_Release+Asserts/include -I/home/Administrator/julia/deps/build/llvm-svn/build_Release+Asserts/lib/IR -I/home/Administrator/julia/deps/srccache/llvm-svn/include -I/home/Administrator/julia/deps/srccache/llvm-svn/lib/IR -D_DEBUG -D__NO_CTYPE_INLINE -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -O2 -fomit-frame-pointer -g -std=gnu++11 -fvisibility-inlines-hidden -fno-exceptions -fno-rtti -Wcast-qual -D__USING_SJLJ_EXCEPTIONS__ -D__CRT__NO_INLINE -pedantic -Wno-long-long -Wall -W -Wno-unused-parameter -Wwrite-strings -Wno-maybe-uninitialized -Wno-missing-field-initializers -Wno-comment -c -MMD -MP -MF "/home/Administrator/julia/deps/build/llvm-svn/build_Release+Asserts+GCC/lib/IR/Release+Debug+Asserts/Instructions.d.tmp" -MT "/home/Administrator/julia/deps/build/llvm-svn/build_Release+Asserts+GCC/lib/IR/Release+Debug+Asserts/Instructions.o" -MT "/home/Administrator/julia/deps/build/llvm-svn/build_Release+Asserts+GCC/lib/IR/Release+Debug+Asserts/Instructions.d" /home/Administrator/julia/deps/srccache/llvm-svn/lib/IR/Instructions.cpp -o /home/Administrator/julia/deps/build/llvm-svn/build_Release+Asserts+GCC/lib/IR/Release+Debug+Asserts/Instructions.o ``` I will try `-fno-strict-aliasing`
