Re: name of m4 executable

[Assar Westerlund <assar at sics dot se>]

Marco Franzen <marcof@thyron.com> writes:
> [Crossposting to gcc-bugs. 
> Gcc's top-level Makefile invokes sub-makes with M4=m4. This overrides
> autoconf's otherwise correct idea of what "m4" it should call.]
> The top-level Makefile of gcc apparently tries to override m4 (for
> autoconf or for something else) with any other m4 that might be present in
> the current build tree. But the default case (no m4 in the tree) hard-codes
> overriding with the value `m4' (without the quotes) rather than not
> overriding.
> 
> The Makefile sets (literally copied from its Makefile.in)
> DEFAULT_M4 = m4
> M4 = `if [ -f $$r/m4/m4 ] ; \
>         then echo $$r/m4/m4 ; \
>         else echo ${DEFAULT_M4} ; fi`

Actually not.  The top-level configure in gcc checks for gm4 gnum4 m4
and replaces DEFAULT_M4 with that value.

Also note that the top-level configure is not an autoconf-generated
configure script but rather a cygnus-style configure.

> On gcc's side, it is still wrong to override m4 with a hard-coded value
> (other than maybe the empty string if that worked). At the very least, if it
> must override it at all, then it should search for suitable m4's at
> configuration time the same way autoconf does.

Since it actually does, the question is why it doesn't work for you.

> - Get the timestamps in the tarball right, so that testers don't need
>   autoconf, bison, etc. 

I think this is what contrib/gcc_update is trying to do?

/assar