- AC_TRY_COMPILE(
- [extern __attribute__((__visibility__("hidden"))) int hiddenvar;
- extern __attribute__((__visibility__("default"))) int exportedvar;
- extern __attribute__((__visibility__("hidden"))) int hiddenfunc (void);
- extern __attribute__((__visibility__("default"))) int exportedfunc (void);],
- [],
- gl_cv_cc_visibility=yes,
- gl_cv_cc_visibility=no)
+ dnl We use the option -Werror and a function dummyfunc, because on some
+ dnl platforms (Cygwin 1.7) the use of -fvisibility triggers a warning
+ dnl "visibility attribute not supported in this configuration; ignored"
+ dnl at the first function definition in every compilation unit, and we
+ dnl don't want to use the option in this case.
+ if test $gl_cv_cc_vis_werror = yes; then
+ CFLAGS="$CFLAGS -Werror"
+ fi
+ AC_COMPILE_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[extern __attribute__((__visibility__("hidden"))) int hiddenvar;
+ extern __attribute__((__visibility__("default"))) int exportedvar;
+ extern __attribute__((__visibility__("hidden"))) int hiddenfunc (void);
+ extern __attribute__((__visibility__("default"))) int exportedfunc (void);
+ void dummyfunc (void) {}
+ ]],
+ [[]])],
+ [gl_cv_cc_visibility=yes],
+ [gl_cv_cc_visibility=no])