1 files changed, 129 insertions, 0 deletions

diff --git a/gl/m4/error_h.m4 b/gl/m4/error_h.m4
new file mode 100644
index 00000000..4ef5cbff
--- /dev/null
+++ b/gl/m4/error_h.m4
@@ -0,0 +1,129 @@
+# error_h.m4
+# serial 5
+dnl Copyright (C) 1996-2025 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+dnl This file is offered as-is, without any warranty.
+
+dnl From Bruno Haible.
+dnl Provide a working <error.h>.
+
+AC_DEFUN_ONCE([gl_ERROR_H],
+[
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+
+  gl_CHECK_NEXT_HEADERS([error.h])
+  if test $ac_cv_header_error_h = yes; then
+    HAVE_ERROR_H=1
+  else
+    HAVE_ERROR_H=0
+  fi
+  AC_SUBST([HAVE_ERROR_H])
+
+  REPLACE_ERROR=0
+
+  gl_CHECK_FUNCS_ANDROID([error], [[#include <error.h>]])
+  if test $ac_cv_func_error = yes; then
+    HAVE_ERROR=1
+  else
+    HAVE_ERROR=0
+    case "$gl_cv_onwards_func_error" in
+      future*) REPLACE_ERROR=1 ;;
+    esac
+  fi
+
+  dnl We don't use AC_FUNC_ERROR_AT_LINE any more, because it is no longer
+  dnl maintained in Autoconf and because it invokes AC_LIBOBJ.
+  dnl We need to notice a missing declaration, like gl_CHECK_FUNCS_ANDROID does.
+  AC_CHECK_DECL([error_at_line], , , [[#include <error.h>]])
+  if test $ac_cv_have_decl_error_at_line = yes; then
+    AC_CACHE_CHECK([for error_at_line], [ac_cv_lib_error_at_line],
+      [AC_LINK_IFELSE(
+         [AC_LANG_PROGRAM(
+            [[#include <error.h>]],
+            [[error_at_line (0, 0, "", 0, "an error occurred");]])],
+         [ac_cv_lib_error_at_line=yes],
+         [ac_cv_lib_error_at_line=no])])
+  else
+    ac_cv_lib_error_at_line=no
+  fi
+  if test $ac_cv_lib_error_at_line = yes; then
+    HAVE_ERROR_AT_LINE=1
+  else
+    HAVE_ERROR_AT_LINE=0
+  fi
+  REPLACE_ERROR_AT_LINE=0
+
+  if test $ac_cv_func_error = yes && test $ac_cv_lib_error_at_line = yes; then
+    dnl On Android 11, when error_print_progname is set, the output of the
+    dnl error() function contains an extra space.
+    AC_CACHE_CHECK([for working error function],
+      [gl_cv_func_working_error],
+      [if test $cross_compiling != yes; then
+         AC_LINK_IFELSE(
+           [AC_LANG_PROGRAM([[
+              #include <error.h>
+              static void print_no_progname (void) {}
+            ]], [[
+              error_print_progname = print_no_progname;
+              error (0, 0, "foo");
+            ]])
+           ],
+           [rm -f conftest.out
+            if test -s conftest$ac_exeext \
+               && ./conftest$ac_exeext 2> conftest.out; then
+              if grep ' ' conftest.out >/dev/null; then
+                gl_cv_func_working_error=no
+              else
+                gl_cv_func_working_error=yes
+              fi
+            else
+              gl_cv_func_working_error=no
+            fi
+            rm -f conftest.out
+           ],
+           [gl_cv_func_working_error=no])
+       else
+         AC_COMPILE_IFELSE(
+           [AC_LANG_PROGRAM([[
+              #include <error.h>
+            ]], [[
+              error (0, 0, "foo");
+            ]])
+           ],
+           [case "$host_os" in
+                               # Guess yes on glibc systems.
+              *-gnu* | gnu*)   gl_cv_func_working_error="guessing yes" ;;
+                               # Guess no on Android.
+              linux*-android*) gl_cv_func_working_error="guessing no" ;;
+                               # If we don't know, obey --enable-cross-guesses.
+              *)               gl_cv_func_working_error="$gl_cross_guess_normal" ;;
+            esac
+           ],
+           [gl_cv_func_working_error=no])
+       fi
+      ])
+    case "$gl_cv_func_working_error" in
+      *no)
+        REPLACE_ERROR=1
+        REPLACE_ERROR_AT_LINE=1
+        ;;
+    esac
+  fi
+
+  m4_ifdef([gl_HAVE_MODULE_VERROR],
+    [COMPILE_ERROR_C=1],
+    [if test $HAVE_ERROR = 0 || test $REPLACE_ERROR = 1 \
+        || test $HAVE_ERROR_AT_LINE = 0 \
+        || test $REPLACE_ERROR_AT_LINE = 1; then
+       COMPILE_ERROR_C=1
+     else
+       COMPILE_ERROR_C=0
+     fi])
+
+  AC_SUBST([HAVE_ERROR])
+  AC_SUBST([HAVE_ERROR_AT_LINE])
+  AC_SUBST([REPLACE_ERROR])
+  AC_SUBST([REPLACE_ERROR_AT_LINE])
+])