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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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struct xx
{
 int x;
 struct yy *p;
 struct
 {
 int s;
 };
 struct
 {
 int s;
 };    
};

int main()
{    
 struct xx xyz;
 printf("%d",sizeof(xyz));
 return 0;
}

the above code compile well without any warning. Here my question is
1. How can I distinguish two 's' variable.
2. What is use case.

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instructions and basic blocks with named labels, then from the compiler plugin I assign named labels to branch instructions and basic blocks, and from symbol table I can get offset to these instructions
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0 votes

Can I use gcc as well as java compiler on a single desktop?

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