Compilation on Ubuntu Xenial 4.4.0-210-generic i386 with gcc version 5.4.0
20160609 (Ubuntu 5.4.0-6ubuntu1~16.04.12) will fail with:
lib/linux/compiler.h:37:34: error: implicit declaration of function
‘__builtin_add_overflow_p’ [-Werror=implicit-function-declaration]
>From the GCC document[1] it looks like this built-in function was only
introduced since 7.1.0
This can be fixed by simply changing the version check from 5.1.0 to 7.1.0
[1] https://gcc.gnu.org/onlinedocs/gcc-7.1.0/gcc/Integer-Overflow-Builtins.html
Signed-off-by: Po-Hsu Lin <po-hsu.lin@xxxxxxxxxxxxx>
---
lib/linux/compiler.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/lib/linux/compiler.h b/lib/linux/compiler.h
index 745792a..5d9552a 100644
--- a/lib/linux/compiler.h
+++ b/lib/linux/compiler.h
@@ -30,7 +30,7 @@
__builtin_mul_overflow(a, b, &__d); \
})
#endif
-#elif GCC_VERSION >= 50100
+#elif GCC_VERSION >= 70100
#define COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW 1
#define check_add_overflow(a, b) __builtin_add_overflow_p(a, b, (typeof((a) + (b)))0)
#define check_sub_overflow(a, b) __builtin_add_overflow_p(a, b, (typeof((a) - (b)))0)
--
2.25.1
