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Valgrind with dynamically linked GCC plugin

+3 votes
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I've been using the profiling tool valgrind for a while now. It requires an executable to run, i.e.

$ valgrind ./a.out

I want to use it on a dynamically linked GCC plugin, and list the time taken and the number of calls by each function used in the plugin. I am running the GCC plugin as follows:

 $ gcc -fplugin=./plugin.so myfile.c

When I run the following command, valgrind reports the memory leaks for only gcc and not for plugin.so. I need a way to run valgrind exclusively on my plugin, which is a .so file.

 $ valgrind gcc -fplugin=./plugin.so myfile.c
 $ gcc -fplugin=./plugin.so myfile.c -wrapper valgrind

Is it even possible to do that? I've searched up on this a lot but haven't found any concrete answer on it.

posted Jun 3, 2015 by Ankit

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1 Answer

+1 vote

gcc is only a driver which runs other binaries to perform actual tasks: preprocessor, compiler, assembler, linker. You have to add --trace-children=yes option when starting gcc, or run it as a wrapper as you wrote above:

valgrind --trace-children=yes gcc -fplugin=./plugin.so myfile.c
answer Aug 12, 2015 by anonymous
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