gcc-4.6.0 Darwin SIGRTMIN is undefined

[gopherbot]

by smirolo:

I looked forward to try out go now that it is an official language supported by gcc but
the code failed to compile on OSX10.6.7+i686-apple-darwin10-gcc-4.2.1 (GCC) 4.2.1 (Apple
Inc. build 5666).

I apologize if the bug should be reported somewhere else (as well? instead of here?). As
the build panel shows an "ok" for darwin systems, I assume there has been a
solution already published. Unfortunately I cannot find any tag matching the released
gcc-4.6.0 so I do not know if it is expected to fail. I couldn't find any information
either on how the hg go repository makes it into the official gcc release so it is
really hard to guess whose bug it is and where a workaround is supposed to live.

curl -O ftp:https://mirrors.kernel.org/gnu/gcc/gcc-4.6.0/gcc-4.6.0.tar.bz2
tar jxvf gcc-4.6.0.tar.bz2
mkdir -p gcc-4.6.0-build
cd gcc-4.6.0-build
export PATH=/usr/bin:/bin:/usr/sbin:/sbin:/usr/X11/bin:/opt/local/bin
~/build/gcc-4.6.0/configure --enable-languages=c,c++,go --with-gmp=/opt/local
--with-mpfr=/opt/local --with-mpc=/opt/local --prefix=${HOME}/build/install/gccgo
make
...
~/build/gcc-4.6.0/libgo/runtime/go-go.c: In function ‘runtime_stoptheworld’:
~/build/gcc-4.6.0/libgo/runtime/go-go.c:386:29: error: ‘SIGRTMIN’ undeclared (first
use in this function)
...

SIGRTMIN as per wikipedia (https://en.wikipedia.org/wiki/SIGRTMIN_and_SIGRTMAX) is
standard POSIX. Unfortunately it isn't defined anywhere on my OSX 10.6.7 system.
grep -r SIGRTMIN /usr/include
[nothing]
More searching actually reveal that real-time signals are not supported on OSX...

[rsc]

Comment 1:

Even if that worked I think you'd run into other problems.
Marking as a duplicate of 463; we'll let that be the
"gccgo doesn't build on Mac" super-bug.

Owner changed to @ianlancetaylor.

Status changed to Duplicate.

Merged into issue #463.