+ dnl BSD getopt_long uses an incompatible method to reset
+ dnl option processing. Existence of the variable, in and of
+ dnl itself, is not a reason to replace getopt, but knowledge
+ dnl of the variable is needed to determine how to reset and
+ dnl whether a reset reparses the environment. Solaris
+ dnl supports neither optreset nor optind=0, but keeps no state
+ dnl that needs a reset beyond setting optind=1; detect Solaris
+ dnl by getopt_clip.
+ AC_COMPILE_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[#include <unistd.h>]],
+ [[int *p = &optreset; return optreset;]])],
+ [gl_optind_min=1],
+ [AC_COMPILE_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[#include <getopt.h>]],
+ [[return !getopt_clip;]])],
+ [gl_optind_min=1],
+ [gl_optind_min=0])])
+
+ dnl This test fails on mingw and succeeds on many other platforms.
+ gl_save_CPPFLAGS=$CPPFLAGS
+ CPPFLAGS="$CPPFLAGS -DOPTIND_MIN=$gl_optind_min"