lli crashes with va_arg when using -force-interpreter=true

[llvmbot]

Bugzilla Link	21197
Version	unspecified
OS	MacOS X
Attachments	Simple vaarg example.
Reporter	LLVM Bugzilla Contributor

Extended Description

When compiling the attached example to bitcode and running it with lli -force-interpreter=true lli crashes. Compiling and running it natively yields the correct output and running it through lli without -force-interpreter=true also yields the expected output.

From running the example with lli -debug and cross checking with the llvm ir, it seems that the va_start implementation used by the interpreter does not initialize the __va_list_tag structure correctly, but I do not know what the correct initialization would look like. (And the crash might have a different cause al to gether).

users-Mac:test user$clang -O0 -emit-llvm -S vaarg.c vaarg.c:12:2: warning: implicit declaration of function 'putchar' is invalid in C99 [-Wimplicit-function-declaration] putchar('0' + i); ^ 1 warning generated. users-Mac:test user$ /usr/local/Cellar/llvm/3.5.0/bin/lli --version LLVM (http://llvm.org/): LLVM version 3.5.0 Optimized build with assertions. Built Sep 21 2014 (23:54:15). Default target: x86_64-apple-darwin13.4.0 Host CPU: core-avx-i users-Mac:test user$ /usr/local/Cellar/llvm/3.5.0/bin/lli -force-interpreter=false ./vaarg.ll 2 users-Mac:test user$ /usr/local/Cellar/llvm/3.5.0/bin/lli -force-interpreter=true ./vaarg.ll 0 libLLVM-3.5.dylib 0x0000000106cb4bb9 llvm::sys::PrintStackTrace(__sFILE) + 40 1 libLLVM-3.5.dylib 0x0000000106cb4fa4 SignalHandler(int) + 248 2 libsystem_platform.dylib 0x00007fff94e045aa _sigtramp + 26 3 libsystem_platform.dylib 000000000000000000 _sigtramp + 1797241456 4 libLLVM-3.5.dylib 0x000000010699d66e llvm::Interpreter::visitLoadInst(llvm::LoadInst&) + 156 5 libLLVM-3.5.dylib 0x00000001069a640c llvm::Interpreter::run() + 156 6 libLLVM-3.5.dylib 0x00000001069a9f04 llvm::Interpreter::runFunction(llvm::Function*, std::__1::vector<llvm::GenericValue, std::__1::allocatorllvm::GenericValue > const&) + 240 7 libLLVM-3.5.dylib 0x00000001068f1c81 llvm::ExecutionEngine::runFunctionAsMain(llvm::Function*, std::__1::vector<std::__1::basic_string<char, std::__1::char_traits, std::__1::allocator >, std::__1::allocator<std::__1::basic_string<char, std::__1::char_traits, std::__1::allocator > > > const&, char const* const*) + 1521 8 lli 0x000000010651c703 9 libdyld.dylib 0x00007fff8fa3c5fd start + 1 Stack dump: 0. Program arguments: /usr/local/Cellar/llvm/3.5.0/bin/lli -force-interpreter=true ./vaarg.ll Segmentation fault: 11

[ratnax]

This happens on latest as well. Does anybody have fix for it ? Thanks