diff --git a/configure b/configure
index 725250b..37c51cc 100755
--- a/configure
+++ b/configure
@@ -6264,6 +6264,8 @@
 # tweak BASECFLAGS based on compiler and platform
 case $GCC in
 yes)
+    BASECFLAGS="$BASECFLAGS -Werror=declaration-after-statement"
+
     # Python doesn't violate C99 aliasing rules, but older versions of
     # GCC produce warnings for legal Python code.  Enable
     # -fno-strict-aliasing on versions of GCC that support but produce
diff --git a/configure.ac b/configure.ac
index 03f9072..647de88 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1127,6 +1127,8 @@
 # tweak BASECFLAGS based on compiler and platform
 case $GCC in
 yes)
+    BASECFLAGS="$BASECFLAGS -Werror=declaration-after-statement"
+
     # Python doesn't violate C99 aliasing rules, but older versions of
     # GCC produce warnings for legal Python code.  Enable
     # -fno-strict-aliasing on versions of GCC that support but produce