Changeset 232599 in webkit

Timestamp:

Jun 7, 2018 2:05:29 PM (6 years ago)

Author:

ddkilzer@apple.com

Message:

bmalloc: Fix 'noreturn' warnings when compiling with -std=gnu++17
<​https://webkit.org/b/186400>

Reviewed by Saam Barati.

Fixes the following warnings when compiling with gnu++17:

Source/bmalloc/bmalloc/Scavenger.cpp:363:1: error: function 'threadRunLoop' could be declared with attribute 'noreturn' [-Werror,-Wmissing-noreturn]
{

^{Source/bmalloc/bmalloc/Scavenger.cpp:358:1: error: function 'threadEntryPoint' could be declared with attribute 'noreturn' [-Werror,-Wmissing-noreturn]
{}

• bmalloc/BCompiler.h:

(BCOMPILER): Add support for the BCOMPILER() macro, then add
BCOMPILER(GCC_OR_CLANG). Taken from Source/WTF/wtf/Compiler.h.
(BNO_RETURN): Implement 'norerturn' support using the new
BCOMPILER() macros. Taken from Source/WTF/wtf/Compiler.h.

• bmalloc/Scavenger.cpp:

(bmalloc::Scavenger::threadRunLoop): Remove the workaround that
tricked older compilers into thinking the while() loop wasn't
infinite.

• bmalloc/Scavenger.h:

(bmalloc::Scavenger::threadEntryPoint): Add BNO_RETURN attribute.
(bmalloc::Scavenger::threadRunLoop): Ditto.

Location:

trunk/Source/bmalloc

Files:

• ChangeLog (modified) (1 diff)
• bmalloc/BCompiler.h (modified) (2 diffs)
• bmalloc/Scavenger.cpp (modified) (1 diff)
• bmalloc/Scavenger.h (modified) (1 diff)

trunk/Source/bmalloc/ChangeLog

@@ +1 @@
+2018-06-07  David Kilzer  <ddkilzer@apple.com>
+
+        bmalloc: Fix 'noreturn' warnings when compiling with -std=gnu++17
+        <https://webkit.org/b/186400>
+
+        Reviewed by Saam Barati.
+
+        Fixes the following warnings when compiling with gnu++17:
+
+            Source/bmalloc/bmalloc/Scavenger.cpp:363:1: error: function 'threadRunLoop' could be declared with attribute 'noreturn' [-Werror,-Wmissing-noreturn]
+            {
+            ^
+            Source/bmalloc/bmalloc/Scavenger.cpp:358:1: error: function 'threadEntryPoint' could be declared with attribute 'noreturn' [-Werror,-Wmissing-noreturn]
+            {
+            ^
+
+        * bmalloc/BCompiler.h:
+        (BCOMPILER): Add support for the BCOMPILER() macro, then add
+        BCOMPILER(GCC_OR_CLANG).  Taken from Source/WTF/wtf/Compiler.h.
+        (BNO_RETURN): Implement 'norerturn' support using the new
+        BCOMPILER() macros.  Taken from Source/WTF/wtf/Compiler.h.
+        * bmalloc/Scavenger.cpp:
+        (bmalloc::Scavenger::threadRunLoop): Remove the workaround that
+        tricked older compilers into thinking the while() loop wasn't
+        infinite.
+        * bmalloc/Scavenger.h:
+        (bmalloc::Scavenger::threadEntryPoint): Add BNO_RETURN attribute.
+        (bmalloc::Scavenger::threadRunLoop): Ditto.
+
 2018-05-29  Saam Barati  <sbarati@apple.com>
 

trunk/Source/bmalloc/bmalloc/BCompiler.h

@@ -26 +26 @@
 #pragma once
 
+/* BCOMPILER() - the compiler being used to build the project */
+#define BCOMPILER(BFEATURE) (defined BCOMPILER_##BFEATURE && BCOMPILER_##BFEATURE)
+
 /* BCOMPILER_HAS_CLANG_FEATURE() - whether the compiler supports a particular language or library feature. */
 /* http://clang.llvm.org/docs/LanguageExtensions.html#has-feature-and-has-extension */
@@ -36 +39 @@
 #define BASAN_ENABLED BCOMPILER_HAS_CLANG_FEATURE(address_sanitizer)
 
+/* BCOMPILER(GCC_OR_CLANG) - GNU Compiler Collection or Clang */
+
+#if defined(__GNUC__)
+#define BCOMPILER_GCC_OR_CLANG 1
+#endif
+
+/* BNO_RETURN */
+
+#if !defined(BNO_RETURN) && BCOMPILER(GCC_OR_CLANG)
+#define BNO_RETURN __attribute((__noreturn__))
+#endif
+
+#if !defined(BNO_RETURN)
+#define BNO_RETURN
+#endif
+

trunk/Source/bmalloc/bmalloc/Scavenger.cpp

@@ -375 +375 @@
     // condition variable and wake us up.
     
-    auto truth = [] { return true; };
-    
-    while (truth()) {
+    while (true) {
         if (m_state == State::Sleep) {
             std::unique_lock<Mutex> lock(m_mutex);

trunk/Source/bmalloc/bmalloc/Scavenger.h

@@ -83 +83 @@
     void scheduleIfUnderMemoryPressureHoldingLock(size_t bytes);
 
-    static void threadEntryPoint(Scavenger*);
-    void threadRunLoop();
+    BNO_RETURN static void threadEntryPoint(Scavenger*);
+    BNO_RETURN void threadRunLoop();
     
     void setSelfQOSClass();