[Mingw-users] Profiling and --with-sysroot (was MXE 2.23 Released)

[Tony T. <ton...@gm...>]

On 28/07/2013, at 10:42 PM, Keith Marshall <kei...@us...> wrote:

> On 28/07/13 09:51, Tony Theodore wrote:
>> Profiling works for something I can test quickly[1], do you have a
>> non-trivial example in mind I could try?
> 
> Not right now.  It was a long time ago, (circa gcc-3.4.x era), but IIRC
> the problem lay in an executable compiled using a --without-sysroot gcc
> cross-build refusing to generate a foo.gcda input file for gcov, (when
> compiled with `mingw32-gcc -fprofile-arcs -ftest-coverage ...'.  This
> problem was not apparent with Danny Smith's native mingw32-gcc, nor when
> cross-built --with-sysroot; I've built my cross compilers with that
> option enabled, since making this discovery.

Indeed, that's still the case. The profiling "-pg" option works by placing the "gmon.out" in the current directory of the exe. The other options, "-fprofile-arcs -ftest-coverage", try to use an absolute path[1] that "--with-sysroot" must set in a sensible manner. To get around this with a non-sysroot cross-compile:

set GCONV_PREFIX=.
set GCONV_PREFIX_STRIP=10 #some large number that consumes the full path
foo.exe

This will create the *gcda files in the current directory.

Cheers,

Tony


[1] http://gcc.gnu.org/onlinedocs/gcc-4.8.1/gcc/Cross_002dprofiling.html#Cross_002dprofiling