Changeset 219791 in webkit

Timestamp:

Jul 23, 2017 2:01:28 PM (7 years ago)

Author:

Michael Catanzaro

Message:

Implement FALLTHROUGH attribute for C with GCC
​https://bugs.webkit.org/show_bug.cgi?id=174555

Reviewed by Darin Adler.

My previous attempt to silence the JSC -Wimplicit-fallthrough warnings failed because they
are coming from a C file, and our FALLTHROUGH macro is only implemented for C++. So
implement it for C as well, using C attribute syntax.

Note this is only possible to do for GCC, because Clang only supports this attribute using
the C++ attribute syntax?.

• wtf/Compiler.h:

Location:

trunk/Source/WTF

Files:

• ChangeLog (modified) (1 diff)
• wtf/Compiler.h (modified) (1 diff)

trunk/Source/WTF/ChangeLog

@@ +1 @@
+2017-07-23  Michael Catanzaro  <mcatanzaro@igalia.com>
+
+        Implement FALLTHROUGH attribute for C with GCC
+        https://bugs.webkit.org/show_bug.cgi?id=174555
+
+        Reviewed by Darin Adler.
+
+        My previous attempt to silence the JSC -Wimplicit-fallthrough warnings failed because they
+        are coming from a C file, and our FALLTHROUGH macro is only implemented for C++. So
+        implement it for C as well, using C attribute syntax.
+ 
+        Note this is only possible to do for GCC, because Clang only supports this attribute using
+        the [[C++ attribute syntax]].
+
+        * wtf/Compiler.h:
+
 2017-07-14  Filip Pizlo  <fpizlo@apple.com>
 

trunk/Source/WTF/wtf/Compiler.h

@@ -213 +213 @@
 #endif
 
+#elif !defined(FALLTHROUGH) && !defined(__cplusplus)
+
+#if COMPILER(GCC)
+#if GCC_VERSION_AT_LEAST(7, 0, 0)
+#define FALLTHROUGH __attribute__ ((fallthrough))
+#endif
+#endif
+
 #endif // !defined(FALLTHROUGH) && defined(__cplusplus) && defined(__has_cpp_attribute)