Merge branch '656-format-security' into 'master'

build: Set -Wformat when testing for -Wformat-security

Closes #656

See merge request GNOME/glib!300

configure.ac

@@ -3408,7 +3408,7 @@ AS_IF([test "x$enable_compile_warnings" != xno], [
    -Wno-bad-function-cast \
    -Werror=declaration-after-statement \
    -Werror=missing-prototypes -Werror=implicit-function-declaration \
-   -Werror=pointer-arith -Werror=init-self -Werror=format-security \
+   -Werror=pointer-arith -Werror=init-self \
    -Werror=format=2 -Werror=missing-include-dirs])
 ])
 AC_SUBST(GLIB_WARN_CFLAGS)

meson.build

@@ -353,7 +353,6 @@ if cc.get_id() == 'gcc' or cc.get_id() == 'clang'
     '-Wno-bad-function-cast',
     '-Werror=declaration-after-statement',
     '-Werror=format=2',
-    '-Werror=format-security',
     '-Werror=implicit-function-declaration',
     '-Werror=init-self',
     '-Werror=missing-include-dirs',