From aeb89f6ad6f3cdefb67b026cbe73de839af692a1 Mon Sep 17 00:00:00 2001
From: Rob Browning <rlb@defaultvalue.org>
Date: Tue, 18 Mar 2025 12:56:31 -0500
Subject: [PATCH] configure: add -Werror=array-bounds to CFLAGS when available

This would have prevented https://bugs.gnu.org/76907

* configure.ac: add -Werror=array-bounds to CFLAGS when available
---
 NEWS         | 5 +++++
 configure.ac | 8 ++++++++
 2 files changed, 13 insertions(+)

diff --git a/NEWS b/NEWS
index 394a7a78d..2adbdf099 100644
--- a/NEWS
+++ b/NEWS
@@ -47,6 +47,11 @@ every line in a file.
 
 * Changes to the distribution
 
+* Build system changes
+
+** -Werror=array-bounds is now added to CFLAGS when available
+   This catches <https://bugs.gnu.org/76907>
+
 * Bug fixes
 
 ** `basename` now checks the suffix against the base name, not the full path
diff --git a/configure.ac b/configure.ac
index f3a05ec70..eb2744b61 100644
--- a/configure.ac
+++ b/configure.ac
@@ -62,6 +62,14 @@ AC_PROG_INSTALL
 AC_PROG_CC
 gl_EARLY
 
+AC_MSG_CHECKING([whether the compiler supports -Werror=array-bounds])
+old_CFLAGS="$CFLAGS"
+CFLAGS="$CFLAGS -Werror=array-bounds"
+AC_COMPILE_IFELSE([AC_LANG_PROGRAM([int foo;], [])],
+  [AC_MSG_RESULT([yes])],
+  [AC_MSG_RESULT([no])
+   CFLAGS="$old_CFLAGS"])
+
 AC_MSG_CHECKING([whether the compiler supports -fexcess-precision=standard])
 old_CFLAGS="$CFLAGS"
 CFLAGS="$CFLAGS -fexcess-precision=standard"