How to generate assembly code with clang in Intel syntax?

c++ assembly x86 clang intel
Jesse Good picture Jesse Good · Jun 12, 2012 · Viewed 48.2k times · Source

As this question shows, with g++, I can do g++ -S -masm=intel test.cpp. Also, with clang, I can do clang++ -S test.cpp, but -masm=intel is not supported by clang (warning argument unused during compilation: -masm=intel). How do I get intel syntax with clang?

Answer

dcoles picture dcoles · Aug 14, 2012

As noted below by @thakis, newer versions of Clang (3.5+) accept the -masm=intel argument.

For older versions, this should get clang to emit assembly code with Intel syntax:

clang++ -S -mllvm --x86-asm-syntax=intel test.cpp

You can use -mllvm <arg> to pass in llvm options from the clang command line. Sadly this option doesn't appear to be well documented, and thus I only found it by browsing through the llvm mailing lists.

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