Wrong configure test for PCH ?

[Carlo Wood]

In libstdc++-v3/acinclude.m4 I see:

AC_DEFUN(GLIBCXX_ENABLE_PCH, [
...

      echo '#include <math.h>' > conftest.h
      if $CXX $CXXFLAGS $CPPFLAGS -x c++-header conftest.h \
             -o conftest.h.gch 1>&5 2>&1 &&
...

I think there is a '-c' missing there.
The above would always fail with:

/usr/lib/crt1.o(.text+0x18): In function `_start':
../sysdeps/i386/elf/start.S:77: undefined reference to `main'
collect2: ld returned 1 exit status

I didn't file a PR because I am not 100% sure, and as soon
as someone agrees, he might as well just add that -c immedeately.

-- 
Carlo Wood <carlo@alinoe.com>