configure.ac: Check for the readline.h explicitly
When readline development package is missing make fails with
"configure: error: system readline is not new enough" which
might be confusing. This patch checks for the readline.h explicitly
and makes make to warn about the missing package.
diff --git a/gdb/config.in b/gdb/config.in
index 773a0ba..4b8f1f7 100644
--- a/gdb/config.in
+++ b/gdb/config.in
@@ -382,6 +382,9 @@
/* Define if Python interpreter is being linked in. */
#undef HAVE_PYTHON
+/* Define to 1 if you have the <readline/readline.h> header file. */
+#undef HAVE_READLINE_READLINE_H
+
/* Define to 1 if you have the `resize_term' function. */
#undef HAVE_RESIZE_TERM
diff --git a/gdb/configure b/gdb/configure
index fe685f2..90c1e3d 100755
--- a/gdb/configure
+++ b/gdb/configure
@@ -9224,6 +9224,23 @@
if test "$with_system_readline" = yes; then
+ for ac_header in readline/readline.h
+do :
+ ac_fn_c_check_header_mongrel "$LINENO" "readline/readline.h" "ac_cv_header_readline_readline_h" "$ac_includes_default"
+if test "x$ac_cv_header_readline_readline_h" = xyes; then :
+ cat >>confdefs.h <<_ACEOF
+#define HAVE_READLINE_READLINE_H 1
+_ACEOF
+ readline_h=yes
+else
+ readline_h=no
+fi
+
+done
+
+ if test "$readline_h" = "no"; then
+ as_fn_error $? "readline development packages are probably missing" "$LINENO" 5
+ fi
{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether system readline is new enough" >&5
$as_echo_n "checking whether system readline is new enough... " >&6; }
if ${gdb_cv_readline_ok+:} false; then :
diff --git a/gdb/configure.ac b/gdb/configure.ac
index 56e8a2d..29c1c45 100644
--- a/gdb/configure.ac
+++ b/gdb/configure.ac
@@ -596,6 +596,10 @@
[use installed readline library])])
if test "$with_system_readline" = yes; then
+ AC_CHECK_HEADERS(readline/readline.h, [readline_h=yes], [readline_h=no])
+ if test "$readline_h" = "no"; then
+ AC_MSG_ERROR([readline development packages are probably missing])
+ fi
AC_CACHE_CHECK(
[whether system readline is new enough],
[gdb_cv_readline_ok],
