AC_PROG_CC failure -- compiler cannot create executables

[Keith Marshall]

What is best recommended practice, to work around the issued described
in this MinGW bug: https://sourceforge.net/p/mingw/bugs/2155/ ?

In summary: building cross-gcc, all up to stage 1 compiler build is
fine, but stage 2 cannot proceed until the host libraries are built.
The stage 1 compiler should suffice to build these, but with current
configure.ac, they need an already existing stage 2 compiler.

I know there's the GCC_NO_EXECUTABLES macro, provided in the GCC sources
themselves -- that's what mingwrt-3.x used -- or there's the even
simpler hack of simply overriding _AC_COMPILER_EXEEXT.  Either of these
seems to work, but neither seems entirely satisfactory, (kludging
around, as they do, with dependencies on undocumented autoconf internals).

MinGW's old w32api-3.x used an alternative avoidance strategy -- using
AC_CHECK_TOOL rather than AC_PROG_CC, to identify the compiler.  This
also has the desired effect -- and with no undocumented dependencies --
but then doesn't capitalize of other useful side effects of AC_PROG_CC.

There seems to be no mention of this in the autoconf manual, beyond a
comment confirming that AC_PROG_CC will fail if the compiler cannot
successfully create executables.  Googling turns up a significant number
of relevant discussions, but there appears to be a deafening silence
from the autoconf development community -- perhaps someone would care to
remedy that omission?

-- 
Regards,
Keith.