diff options
Diffstat (limited to 'gnulib-m4/warn-on-use.m4')
| -rw-r--r-- | gnulib-m4/warn-on-use.m4 | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/gnulib-m4/warn-on-use.m4 b/gnulib-m4/warn-on-use.m4 index d43355ab..a81731f3 100644 --- a/gnulib-m4/warn-on-use.m4 +++ b/gnulib-m4/warn-on-use.m4 @@ -1,4 +1,4 @@ -# warn-on-use.m4 serial 9 +# warn-on-use.m4 serial 10 dnl Copyright (C) 2010-2022 Free Software Foundation, Inc. dnl This file is free software; the Free Software Foundation dnl gives unlimited permission to copy and/or distribute it, @@ -32,17 +32,30 @@ AC_DEFUN([gl_WARN_ON_USE_PREPARE], undefining macros.])])dnl for gl_func in m4_flatten([$2]); do AS_VAR_PUSHDEF([gl_Symbol], [gl_cv_have_raw_decl_$gl_func])dnl + dnl As a workaround to implicit built-in function declarations in + dnl clang (e.g. strndup), reference ac_compile_for_check_decl instead + dnl of ac_compile. If, for whatever reason, the override of AC_PROG_CC + dnl in zzgnulib.m4 is inactive, use the original ac_compile. + ac_save_ac_compile="$ac_compile" + if test -n "$ac_compile_for_check_decl"; then + ac_compile="$ac_compile_for_check_decl" + fi AC_CACHE_CHECK([whether $gl_func is declared without a macro], [gl_Symbol], [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([$1], [[#undef $gl_func (void) $gl_func;]])], [AS_VAR_SET([gl_Symbol], [yes])], [AS_VAR_SET([gl_Symbol], [no])])]) + ac_compile="$ac_save_ac_compile" AS_VAR_IF([gl_Symbol], [yes], [AC_DEFINE_UNQUOTED(AS_TR_CPP([HAVE_RAW_DECL_$gl_func]), [1]) - dnl shortcut - if the raw declaration exists, then set a cache - dnl variable to allow skipping any later AC_CHECK_DECL efforts - eval ac_cv_have_decl_$gl_func=yes]) + dnl Shortcut for an AC_CHECK_DECL invocation that may come later: + dnl If the raw declaration exists with the given includes, then + dnl AC_CHECK_DECL with its many includes would see it as well. + dnl So, set a cache variable to allow skipping any later + dnl AC_CHECK_DECL invocation for $gl_func. + eval "ac_cv_have_decl_$gl_func=yes" + ]) AS_VAR_POPDEF([gl_Symbol])dnl done ]) |