Error when building llvm x-ray instrument

Question

Following the instructions from llvm XRay instrument guide, I am stuck on the part

cmake -GNinja ../llvm -DCMAKE_BUILD_TYPE=Release \ -DCMAKE_C_FLAGS_RELEASE="-fxray-instrument" -DCMAKE_CXX_FLAGS="-fxray-instrument" \

as it is giving me c++: error: unrecognized command line option '-fxray-instrument.

I have already built the latest llvm project which has the XRay in the tool directory and I used the "Unix Makefiles" option instead of Ninja.

use -DCMAKE_C_COMPILER=/path/clang and -DCMAKE_CXX_COMPILER=/path/clang++ flags with cmake. — DTharun, Mar 08 '19 at 11:56

score 0 · Answer 1 · answered Mar 08 '19 at 05:58

0

Well, the first sentence says

To debug an application with XRay instrumentation, we need to build it with a Clang that supports the -fxray-instrument option.

You, obviously, are using non-clang compiler, which doesn't support this option flag.

answered Mar 08 '19 at 05:58

arrowd

1 Answers1