compiler: -Wlogical-op hardening

Warn about suspicious uses of logical operators in expressions.

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

diff --git a/configure.ac b/configure.ac
index 9a6ba83c2df437160f7caa28af93beef6d54ab13..6aee94be37e2691c3393976823b801a1fcff33d3 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -690,6 +690,7 @@ AC_PROG_SED
 # See if we support thread-local storage.
 LXC_CHECK_TLS
 
+# Hardening flags
 AX_CHECK_COMPILE_FLAG([-fdiagnostics-color], [CFLAGS="$CFLAGS -fdiagnostics-color"],,[-Werror])
 AX_CHECK_COMPILE_FLAG([-Wimplicit-fallthrough], [CFLAGS="$CFLAGS -Wimplicit-fallthrough"],,[-Werror])
 AX_CHECK_COMPILE_FLAG([-Wcast-align], [CFLAGS="$CFLAGS -Wcast-align"],,[-Werror])
@@ -700,6 +701,7 @@ AX_CHECK_LINK_FLAG([-fstack-protector-strong], [CFLAGS="$CFLAGS -fstack-protecto
 AX_CHECK_COMPILE_FLAG([-g], [CFLAGS="$CFLAGS -g"],,[-Werror])
 AX_CHECK_COMPILE_FLAG([--mcet -fcf-protection], [CFLAGS="$CFLAGS --mcet -fcf-protection"],,[-Werror])
 AX_CHECK_COMPILE_FLAG([-Werror=implicit-function-declaration], [CFLAGS="$CFLAGS -Werror=implicit-function-declaration"],,[-Werror])
+AX_CHECK_COMPILE_FLAG([-Wlogical-op], [CFLAGS="$CFLAGS -Wlogical-op"],,[-Werror])
 
 AX_CHECK_LINK_FLAG([-z relro], [LDLAGS="$LDLAGS -z relro"],,[])
 AX_CHECK_LINK_FLAG([-z now], [LDLAGS="$LDLAGS -z now"],,[])