util: Add attribute warn_unused_result to allocation functions

Add the warn_unused_result GCC function attribute to all allocation
functions in xmalloc.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>

2 files changed, 5 insertions, 4 deletions

diff --git a/compiler.h b/compiler.h
index a6bf3a6..3559050 100644
--- a/compiler.h
+++ b/compiler.h
@@ -21,6 +21,7 @@
 
 #ifdef __GNUC__
 # define __noreturn		__attribute__((noreturn))
+# define __warn_unused_result	__attribute__((warn_unused_result))
 # define __packed		__attribute__((packed))
 # define __unused		__attribute__((unused))
 # ifndef offsetof
diff --git a/util.h b/util.h
index d4933c4..0c3d263 100644
--- a/util.h
+++ b/util.h
@@ -58,10 +58,10 @@ static inline void __noreturn panic(const char *fmt, ...)
 	exit(EXIT_FAILURE);
 }
 
-void *xmalloc(size_t size);
-void *xzalloc(size_t size);
-void *xrealloc(void *ptr, size_t size);
-char *xstrdup(const char *s);
+void *xmalloc(size_t size) __warn_unused_result;
+void *xzalloc(size_t size) __warn_unused_result;
+void *xrealloc(void *ptr, size_t size) __warn_unused_result;
+char *xstrdup(const char *s) __warn_unused_result;
 
 static inline bool xstreq(const char *str1, const char *str2)
 {