Enable subset of flags with low performance impact and no warnings

configure.ac

@@ -2451,6 +2451,18 @@ AS_VAR_IF([with_strict_overflow], [yes],
           [BASECFLAGS="$BASECFLAGS $STRICT_OVERFLOW_CFLAGS"],
           [BASECFLAGS="$BASECFLAGS $NO_STRICT_OVERFLOW_CFLAGS"])
 
+
+# Enable flags that warn and protect for potential security vulnerabilities.
+# These flags should be enabled by default for all builds.
+AX_CHECK_COMPILE_FLAG([-Wimplicit-fallthrough], [BASECFLAGS="$BASECFLAGS -Wimplicit-fallthrough"], [AC_MSG_WARN([-Wimplicit-fallthrough not supported])])
+AX_CHECK_COMPILE_FLAG([-fstack-protector-strong], [BASECFLAGS="$BASECFLAGS -fstack-protector-strong"], [AC_MSG_WARN([-fstack-protector-strong not supported])])
+AX_CHECK_COMPILE_FLAG([-fno-strict-overflow], [BASECFLAGS="$BASECFLAGS -fno-strict-overflow"], [AC_MSG_WARN([-fno-strict-overflow not supported])])
+case $CC in
+  *gcc*)
+    # Add GCC-specific compiler flags          
+    AX_CHECK_COMPILE_FLAG([-Wtrampolines], [BASECFLAGS="$BASECFLAGS -Wtrampolines"], [AC_MSG_WARN([-Wtrampolines not supported])])
+esac
+
 case $GCC in
 yes)
     CFLAGS_NODIST="$CFLAGS_NODIST -std=c11"