fix: disable stringop-overread for gcc11

Author: UdjinM6

configure.ac

@@ -457,6 +457,15 @@ if test "x$enable_werror" = "xyes"; then
   AX_CHECK_COMPILE_FLAG([-Werror=return-type], [], [ERROR_CXXFLAGS="$ERROR_CXXFLAGS -Wno-error=return-type"], [$CXXFLAG_WERROR],
                         [AC_LANG_SOURCE([[#include <cassert>
                                           int f(){ assert(false); }]])])
+  dnl -Wstringop-overread is broken in GCC 11.
+  AC_COMPILE_IFELSE(
+    [AC_LANG_PROGRAM([[]],
+         [[#if __GNUC__ == 11
+           #error -Wstringop-overread is broken in GCC 11
+           #endif
+          ]])],
+    [],
+    [ERROR_CXXFLAGS="$ERROR_CXXFLAGS -Wno-stringop-overread"])
 fi
 
 if test "x$CXXFLAGS_overridden" = "xno"; then