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Comment by DaveFlater

Uh... [Begin flashback] 2012: A change made in GCC 4.7 allowed optimization to reschedule and defer the push of the frame pointer that previously occurred in the function prologue whenever frame pointers were enabled. When binaries are profiled using frame pointers, incorrect call chains are derived whenever a sample is taken between the top of the function and the instruction that pushes the frame pointer. I complained, but got an immediate WONTFIX: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=55667

So did they fix that eventually or is everyone just oblivious?

How I found the problem in 2012: Configuration of profiling tools for C/C++ applications under 64-bit Linux https://doi.org/10.6028/NIST.TN.1790

parent DaveFlater 3 years ago

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