AC_LANG_PROGRAM(C): function 'main' without prototype

[Nico R.]

Hello!

When I tried to compile glibc-2.6.1 (with NPTL support) with CFLAGS 
including ‘-Wstrict-prototypes’, I noticed that a configure test failed 
which should have succeeded. I could track the problem down to 
AC_LANG_PROGRAM(C) in c.m4 from autoconf:

AC_LANG_PROGRAM(C) uses a ‘main’ function without a prototype. If CFLAGS 
contains ‘-Werror’ (it does in my case, because the configure script in 
the glibc package adds it), a test using AC_LANG_PROGRAM(C), for example 
AC_LINK_IFELSE, fails.

Shouldn’t the line
  main ()
be
  main (void)
instead? Or may this cause problems with some compilers? Should 
‘-Wstrict-prototypes’ be removed from CFLAGS instead? And should this be 
fixed in autoconf or should I report a bug against glibc?

I examined autoconf-2.61; the problem may be present in other versions 
as well.

Thanks
--
Nico