Profiling: main() vanishes from tree when using optimization about amiga-gcc HOT 10 CLOSED

I get

index % time    self  children    called     name
                0.00    0.00       1/1           main [52]
[1]      0.0    0.00    0.00       1         fct_1 [1]
                0.00    0.00       1/1           fct_2 [2]                                                                                                                                   ```

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I see. So it might be a problem of gprof2dot visualizer? I just asked there.

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any news here?

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I opened an issue here:
jrfonseca/gprof2dot#55

No comments do far.

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please retest

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you might retest this due to the recent changes, no?

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We just got a reply from jrfonseca/gprof2dot#55

There are 2 problems here:

gprof couldn't figure out who called strlen. Perhaps because libc had no debug information, or due to some limitation with m68k architecture (e.g., no stack frame pointer by default)?

gprof lists main as a caller (ie, an edge on the call graph), but didn't create a node for it in the report. No idea why. I never seen this with x86. Perhaps gprof's -c/--static-call-graph help.

Both issues are in gcc/gprof domain, not the gprof2dot tool. The missing main issue is minor IMO. But the strlen is a showstopper -- if time spent in libc functions is not accurately billed to the callers, then the whole graph will end up biased and useless.

I hope this helps.

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then you need libs compiled with -pg.
not a real issue.

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I don't understand why main gets lost when compiling with any optimization level, but yes, it seems compiling libnix with -pg seems to help. So we can close this issue.

Would it make sense to compile the libs (libnix) additionally with -pg during toolchain-installation and use this -pg-compiled version automatically when compiling an executable with -pg?

(I currently build two versions (-g and -pg) of libnix into different directories and have a symbolic link "libnix" pointing to of these two directories)

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IMHO it's easier to use two independent toolchains in different prefixes.

• with pg
• without pg

that way you have it handy for all variants (baserel, 020, math, etc.p.p.) , just use the prefix you want.

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