gcc -g -O3 -fstack-protector --param=ssp-buffer-size=4 -Wformat -Werror=format-security -D_FORTIFY_SOURCE=2 -c test-d.c
gcc -Wl,-z,relro -o test test-a.o test-b.o test-c.o -ltest
+# -Wformat=2 implies -Wformat.
+gcc -g -O2 -fstack-protector --param=ssp-buffer-size=4 -Wformat=2 -Werror=format-security -D_FORTIFY_SOURCE=2 -c test.c
+
# Compiling and linking in one step must also check CFLAGS/CPPFLAGS.
gcc -g -O2 -fstack-protector --param=ssp-buffer-size=4 -Wformat -Wformat-security -Werror=format-security -D_FORTIFY_SOURCE=2 -Wl,-z,relro -o test test.c -ltest
gcc -g -O2 -fstack-protector --param=ssp-buffer-size=4 -Wformat -Wformat-security -Werror=format-security -D_FORTIFY_SOURCE=2 -shared -fPIC -Wl,-z,relro -o test.so test.c -ltest