20990 2008-09-22 06:54:08 -0700 FreeBSD Alpha, >3000 cast alignment warnings on build, unaligned access errors on run 2022-07-11 15:17:25 -0700 1 1 1 Unclassified WebKit JavaScriptCore 528+ (Nightly build) Other Other UNCONFIRMED DoNotImportToRadar P2 Normal --- 0 mexas webkit-unassigned ap bfulgham oldest_to_newest 92120 0 mexas 2008-09-22 06:54:08 -0700 I built webkit-gtk2-0.0.30549_1 from ports on FreeBSD 6.3-stable on Alpha. I had 3293 alignment warnings. The details are below. I use webkit with kazehakase web browser, also built from ports. Kazehakase was built with xulrunner as well. When I ran kazehakase with xulrunner all is well. With webkit I get literally hundreds of messages like this: pid 83623 (kazehakase): unaligned access: va=0x1661aa90e pc=0x164855bb8 ra=0x1648550ac op=ldl or ** (gecko:83623): CRITICAL **: void webkit_web_view_open(WebKitWebView*, const gchar*): assertion `uri' failed With webkit, kazehakase does not load pages, and is otherwise not very responsive. I wonder if the alignment warnings on build show themselves as unaligned access errors on run? ****************************** The alignment warning statistics on build; "log" is the file with all build output. # grep -c alignment log 3293 of which the major culprits are: #grep -c "./JavaScriptCore/wtf/Vector.h:380: warning: cast from" log 1414 #grep -c "WebCore/platform/text/StringHash.h:45: warning: cast from" log 642 #grep -c "WebCore/platform/text/StringHash.h:46: warning: cast from" log 642 #grep -c "./JavaScriptCore/wtf/ListHashSet.h:169: warning: cast from" log 586 and the minor worries are: #grep -c "JavaScriptCore/kjs/dtoa.cpp:2575: warning: cast from" log 2 #grep -c "WebCore/platform/text/AtomicString.cpp:117: warning: cast from" log 1 #grep -c "WebCore/platform/text/AtomicString.cpp:118: warning: cast from" log 1 #grep -c "WebCore/rendering/RenderLayer.cpp:113: warning: cast from" log 1 #grep -c "WebCore/rendering/RootInlineBox.cpp:56: warning: cast from" log 1 #grep -c "JavaScriptCore/pcre/pcre_compile.cpp:2523: warning: cast from" log 1 #grep -c "JavaScriptCore/kjs/property_map.cpp:111: warning: cast from" log 1 #grep -c "./JavaScriptCore/wtf/FastMalloc.cpp:2141: warning: cast from" log 1 642+642+1414+586+2+7*1 = 3293 many thanks anton 92129 1 ap 2008-09-22 08:07:33 -0700 See also: bug 19775. 92486 2 mexas 2008-09-24 01:28:02 -0700 (In reply to comment #1) > See also: bug 19775. > thanks. Regarding this fix: +#if PLATFORM(ARM) || PLATFORM(SPARC64) + const UChar* aChars = a->characters(); + const UChar* bChars = b->characters(); + for (unsigned i = 0; i != aLength; ++i) + if (*aChars++ != *bChars++) + return false; + + return true; +#else what shall I use for PLATFORM,- FREEBSD or ALPHA ? thanks 92523 3 ap 2008-09-24 08:12:10 -0700 I think the latter would be correct, as FreeBSD on other platforms doesn't need this change (which likely affects performance negatively). 92707 4 mexas 2008-09-25 06:51:04 -0700 (In reply to comment #1) > See also: bug 19775. > The patches to JavaScriptCore/wtf/Vector.h: WebCore/platform/text/StringHash.h were successful. I reduced the number of alignment warnings from >3000 down to 600. However, the patch for JavaScriptCore/wtf/ListHashSet.h is not having the effect: ./JavaScriptCore/wtf/ListHashSet.h:169: warning: cast from 'uint32_t*' to 'WTF::ListHashSetNode<WebCore::HTMLFormControlElementWithState*>*' increases required alignment of target type I applied the patch just as in bug report 19775: --- JavaScriptCore/wtf/ListHashSet.h.orig Tue Jul 8 23:23:01 2008 +++ JavaScriptCore/wtf/ListHashSet.h Tue Jul 8 23:24:03 2008 @@ -122,7 +122,7 @@ namespace WTF { : m_freeList(pool()) , m_isDoneWithInitialFreeList(false) { - memset(m_pool.pool, 0, sizeof(m_pool.pool)); + memset(m_pool, 0, sizeof(m_pool)); } Node* allocate() @@ -166,7 +166,7 @@ namespace WTF { } private: - Node* pool() { return reinterpret_cast<Node*>(m_pool.pool); } + Node* pool() { return reinterpret_cast<Node*>(m_pool); } Node* pastPool() { return pool() + m_poolSize; } bool inPool(Node* node) @@ -177,10 +177,7 @@ namespace WTF { Node* m_freeList; bool m_isDoneWithInitialFreeList; static const size_t m_poolSize = 256; - union { - char pool[sizeof(Node) * m_poolSize]; - double forAlignment; - } m_pool; + uint32_t m_pool[(sizeof(Node) * m_poolSize + sizeof(uint32_t) - 1) / sizeof(uint32_t)]; }; template<typename ValueArg> struct ListHashSetNode { Line 169 is the one with reinterpred_cast. Not sure what to do next. anton