[PATCH RESEND] configure: escape square brackets.

[Torbjorn Granlund]

nisse at lysator.liu.se (Niels Möller) writes:

  I'd suggest avoiding the M4 problem by writing the prototype as
  
    main (int argc, char **argv)
  
  which should be entirely equivalent to a C compiler.
  
  Not sure why this test is needed at all, though, since the autoconf
  macro AC_PROG_CC sets ac_cv_prog_cc_c89 if the compiler accepts ansi C
  (and it also tries some random flags to enable ansi-mode of the
  compiler).
  
For now, I used the ** form, and let the redundant macro stay.

(Committed to the GMP repository.)

-- 
Torbjörn