On Solaris 10, with GCC 4.2 and GCC 4.4, any application I compile
*always* has the _mcount symbol, which if I understand correctly
should only be present if my application is being built with
profiling. I've verified that I don't see this behavior on Linux, only
on Solaris, and I've double checked that gcc/g++ aren't aliased in my
shell. I am also linking no libraries explicitly. If I run ldd on the
resulting executable, and then run nm on all of the listed shared
libraries (libc and such) none of them contain the symbol _mcount,
although one does contain the symbol _mcount_newent.
Any idea why this would be happening? I have a post-build script that
verifies that _mcount is not present when the profile setting is off,
to ensure that my build system is working correctly. I could remove
it, but I don't want to do so unless this symbol is really supposed to
be present.
mytest.cpp:
int main () { return 0; }
$ g++ -O2 mytest.cpp
$ nm a.out | grep _mcount
[65] | 134547444| 1|FUNC |GLOB |0 |11 |_mcount
$ ldd a.out
libstdc++.so.6 => /opt/app/g++lib6/lib/libstdc++.so.6
libm.so.2 => /lib/libm.so.2
libgcc_s.so.1 => /opt/app/nonc++/lib/libgcc_s.so.1
libc.so.1 => /lib/libc.so.1
$ nm /opt/app/g++lib6/lib/libstdc++.so.6 | grep _mcount
$ nm /lib/libm.so.2 | grep _mcount
$ nm /opt/app/nonc++/lib/libgcc_s.so.1 | grep _mcount
$ nm /lib/libc.so.1 | grep _mcount
[392] | 285460| 70|FUNC |LOCL |2 |11 |_mcount_newent
