configure: fix -Wimplicit-fallthrough check

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

diff --git a/configure.ac b/configure.ac
index 8264c7c486db86e40e1c0818f6a10c192f136ab4..43c2b199f0bd5990a2b31e47faed5390915293db 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -684,7 +684,7 @@ AC_PROG_SED
 LXC_CHECK_TLS
 
 AX_CHECK_COMPILE_FLAG([-fdiagnostics-color], [CFLAGS="$CFLAGS -fdiagnostics-color"],,[-Werror])
-AX_CHECK_COMPILE_FLAG([-implicit-fallthrough], [CFLAGS="$CFLAGS -Wimplicit-fallthrough"],,[-Werror])
+AX_CHECK_COMPILE_FLAG([-Wimplicit-fallthrough], [CFLAGS="$CFLAGS -Wimplicit-fallthrough"],,[-Werror])
 AX_CHECK_COMPILE_FLAG([-Wcast-align], [CFLAGS="$CFLAGS -Wcast-align"],,[-Werror])
 AX_CHECK_COMPILE_FLAG([-Wstrict-prototypes], [CFLAGS="$CFLAGS -Wstrict-prototypes"],,[-Werror])
 

diff --git a/src/lxc/compiler.h b/src/lxc/compiler.h
index 5d1c0561ba493cd5a142212e8f33df8f9ebc9c43..7fd5ea131502ac2cc260f3f9f8007068376ff69e 100644 (file)
--- a/src/lxc/compiler.h
+++ b/src/lxc/compiler.h
@@ -37,10 +37,8 @@
 #endif
 #endif
 
-#if defined(__GNUC__) && __GNUC__ >= 7 || defined(__clang__)
-#define __fallthrough __attribute__((fallthrough))
-#else
-#define __fallthrough
+#ifndef __fallthrough
+#define __fallthrough /* fall through */
 #endif
 
 #ifndef __noreturn