On 11/11/20 10:03 PM, Marek Polacek wrote:
I'd like to have the option of marking functions with
__attribute__ ((__warn_unused_result__)), so this patch adds a macro.
And use it for maybe_wrap_with_location, it's always a bug if the
return value is not used, which happened to me and got me confused.
Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk?
OK.
gcc/ChangeLog:
* system.h (WARN_UNUSED_RESULT): Define for GCC >= 3.4.
* tree.h (maybe_wrap_with_location): Add WARN_UNUSED_RESULT.
---
gcc/system.h | 6 ++++++
gcc/tree.h | 2 +-
2 files changed, 7 insertions(+), 1 deletion(-)
diff --git a/gcc/system.h b/gcc/system.h
index b0f3f1dd019..6f6ab616a61 100644
--- a/gcc/system.h
+++ b/gcc/system.h
@@ -789,6 +789,12 @@ extern void fancy_abort (const char *, int, const char *)
#define ALWAYS_INLINE inline
#endif
+#if GCC_VERSION >= 3004
+#define WARN_UNUSED_RESULT __attribute__ ((__warn_unused_result__))
+#else
+#define WARN_UNUSED_RESULT
+#endif
+
/* Use gcc_unreachable() to mark unreachable locations (like an
unreachable default case of a switch. Do not use gcc_assert(0). */
#if (GCC_VERSION >= 4005) && !ENABLE_ASSERT_CHECKING
diff --git a/gcc/tree.h b/gcc/tree.h
index 684be10b440..9a713cdb0c7 100644
--- a/gcc/tree.h
+++ b/gcc/tree.h
@@ -1214,7 +1214,7 @@ get_expr_source_range (tree expr)
extern void protected_set_expr_location (tree, location_t);
extern void protected_set_expr_location_if_unset (tree, location_t);
-extern tree maybe_wrap_with_location (tree, location_t);
+WARN_UNUSED_RESULT extern tree maybe_wrap_with_location (tree, location_t);
extern int suppress_location_wrappers;
base-commit: 0f5f9ed5e5a041b636cc002451b1e8b2295f8e4f
