Building aarch64 using gcc I get this:
In file included from /u1/src/external/apache2/llvm/librt/libLLVMAnalysis/../../ lib/../dist/llvm/include/llvm/IR/Attributes.h:22, from /u1/src/external/apache2/llvm/librt/libLLVMAnalysis/../../ lib/../dist/llvm/include/llvm/IR/CallSite.h:31, from /u1/src/external/apache2/llvm/librt/libLLVMAnalysis/../../ lib/../dist/llvm/include/llvm/Analysis/ValueTracking.h:20, from /u1/src/external/apache2/llvm/librt/libLLVMAnalysis/../../ lib/../dist/llvm/lib/Analysis/ValueTracking.cpp:14: In member function 'size_t llvm::StringRef::find(char, size_t) const', inlined from 'bool llvm::getConstantStringInfo(const llvm::Value*, llvm::Str ingRef&, uint64_t, bool)' at /u1/src/external/apache2/llvm/librt/libLLVMAnalysis /../../lib/../dist/llvm/lib/Analysis/ValueTracking.cpp:3580:39: /u1/src/external/apache2/llvm/librt/libLLVMAnalysis/../../lib/../dist/llvm/inclu de/llvm/ADT/StringRef.h:309:37: error: 'void* memchr(const void*, int, size_t)' specified size 18446744073709551615 exceeds maximum object size 9223372036854775 807 [-Werror=stringop-overflow=] if (const void *P = ::memchr(Data + FindBegin, C, Length - FindBegin)) ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The 18446744073709551615 value is FFFFFFFFFFFFFFFF. Have built with MKLLVMRT=no for now.