[build] use -fstack-protector-strong w/ extra warn

use -fstack-protector-strong if configured with --enable-extra-warnings

configure.ac

@@ -1623,6 +1623,7 @@ AC_ARG_ENABLE([extra-warnings],
 
 if test "$extrawarnings" = true || test "$extrawarnings" = error; then
   TRY_CFLAGS([-g -O2 -g2 -Wall -Wmissing-declarations -Wcast-align -Wsign-compare -Wnested-externs -Wpointer-arith -D_FORTIFY_SOURCE=2 -fstack-protector --param=ssp-buffer-size=4 -Wformat -Werror=format-security])
+  TRY_CFLAGS([-fstack-protector-strong])
   case "$host_os" in
     *darwin* ) ;;
     * ) TRY_LDFLAGS([-Wl,--as-needed]) ;;

meson_options.txt

@@ -151,7 +151,7 @@ option('build_extra_warnings',
 )
 option('warn_cflags',
 	type: 'string',
-	value: '-g -g2 -Wall -Wmissing-declarations -Wcast-align -Wsign-compare -Wnested-externs -Wpointer-arith -D_FORTIFY_SOURCE=2 -fstack-protector --param=ssp-buffer-size=4 -Wformat -Werror=format-security',
+	value: '-g -g2 -Wall -Wmissing-declarations -Wcast-align -Wsign-compare -Wnested-externs -Wpointer-arith -D_FORTIFY_SOURCE=2 -fstack-protector-strong --param=ssp-buffer-size=4 -Wformat -Werror=format-security',
 	description: 'CFLAGS to use when build_extra_warnings is active',
 )
 

src/CMakeLists.txt

@@ -52,7 +52,7 @@ if(CMAKE_C_COMPILER_ID MATCHES "GNU" OR CMAKE_C_COMPILER_ID MATCHES "Clang")
 	option(BUILD_SANITIZE_UNDEFINED "Enable undefined sanitizer" OFF)
 
 	if(BUILD_EXTRA_WARNINGS)
-		set(WARN_CFLAGS "-g -g2 -Wall -Wmissing-declarations -Wcast-align -Wsign-compare -Wnested-externs -Wpointer-arith -D_FORTIFY_SOURCE=2 -fstack-protector --param=ssp-buffer-size=4 -Wformat -Werror=format-security")
+		set(WARN_CFLAGS "-g -g2 -Wall -Wmissing-declarations -Wcast-align -Wsign-compare -Wnested-externs -Wpointer-arith -D_FORTIFY_SOURCE=2 -fstack-protector-strong --param=ssp-buffer-size=4 -Wformat -Werror=format-security")
 		set(WARN_LDFLAGS "")
 		# -Werror -Wbad-function-cast -Wmissing-prototypes
 		if(NOT BUILD_SANITIZE_ADDRESS)