This bug is just for the warnings in various source files in extensions/xmlextras/base/src. Currently (http://tinderbox.mozilla.org/SeaMonkey/warn1014136200.29882.html - Tue, 19 Feb 2002 11:30 EST) TBox shows the following warnings: extensions/xmlextras/base/src/nsDOMParser.cpp:368 `class nsISupports * foundInterface' might be used uninitialized in this function extensions/xmlextras/base/src/nsDOMSerializer.cpp:66 `class nsISupports * foundInterface' might be used uninitialized in this function extensions/xmlextras/base/src/nsXMLHttpRequest.cpp:156 `class nsISupports * foundInterface' might be used uninitialized in this function

Bug 59652 is the meta-bug tracking the fight against these (potentially very nasty) warnings. P.S. Trying to make sure that 1.0 has as little warnings as possible.

I think the compiler is mistaken. The macro use: NS_INTERFACE_MAP_BEGIN(nsDOMSerializer) NS_INTERFACE_MAP_ENTRY(nsISupports) NS_INTERFACE_MAP_ENTRY(nsIDOMSerializer) NS_INTERFACE_MAP_ENTRY_DOM_CLASSINFO(DOMSerializer) NS_INTERFACE_MAP_END expands (as far as I can tell) into NS_IMETHODIMP nsDOMSerializer::QueryInterface(REFNSIID aIID, void** aInstancePtr) { NS_ASSERTION(aInstancePtr, "QueryInterface requires a non-NULL destination!"); if ( !aInstancePtr ) return NS_ERROR_NULL_POINTER; nsISupports* foundInterface; if ( aIID.Equals(NS_GET_IID(nsISupports)) ) foundInterface = NS_STATIC_CAST(nsISupports*, this); else if ( aIID.Equals(NS_GET_IID(nsIDOMSerializer)) ) foundInterface = NS_STATIC_CAST(nsIDOMSerializer*, this); else if (aIID.Equals(NS_GET_IID(nsIClassInfo))) { foundInterface = nsContentUtils::GetClassInfoInstance(eDOMClassInfo_DOMSerializer_id); NS_ENSURE_TRUE(foundInterface, NS_ERROR_OUT_OF_MEMORY); *aInstancePtr = foundInterface; return NS_OK; } else foundInterface = 0; nsresult status; if ( !foundInterface ) status = NS_NOINTERFACE; else { NS_ADDREF(foundInterface); status = NS_OK; } *aInstancePtr = foundInterface; return status; } so foundInterface is set before use. Initializing it to 0 on declaration might clear the warning, but that would be needless work. I don't have Linux available to test, and the Windows build does not give that warning.

No, you got the code wrong. The actual code (as produced by doing c++ -E and then pretty-printing by hand) is nsresult nsDOMSerializer::QueryInterface(const nsIID& aIID, void** aInstancePtr) { ; if ( !aInstancePtr ) return ((nsresult) 0x80004003L); nsISupports* foundInterface; if ( aIID.Equals(nsCOMTypeInfo<nsISupports>::GetIID()) ) foundInterface = static_cast< nsISupports* >(this); else if ( aIID.Equals(nsCOMTypeInfo<nsIDOMSerializer>::GetIID()) ) foundInterface = static_cast< nsIDOMSerializer* >(this); else if (aIID.Equals(nsCOMTypeInfo<nsIClassInfo>::GetIID())) { static const nsCID kDOMSOF_CID = { 0x9eb760f0, 0x4380, 0x11d2, {0xb3, 0x28, 0x00, 0x80, 0x5f, 0x8a, 0x38, 0x59} }; nsCOMPtr<nsIDOMScriptObjectFactory> sof(do_GetService(kDOMSOF_CID)); if (sof) { foundInterface = sof->GetClassInfoInstance(eDOMClassInfo_DOMSerializer_id); if (foundInterface) { *aInstancePtr = foundInterface; return 0; } } } else foundInterface = 0; nsresult status; if ( !foundInterface ) status = ((nsresult) 0x80004002L); else { (foundInterface)->AddRef(); status = 0; } *aInstancePtr = foundInterface; return status; } Note that if nsIClassInfo branch is chosen, but sof turnes out to be NULL, foundInterface will indeed stay uninitialized...

Thanks, I don't know how I got the expanded code I did. This fix should do it.

Argh, logic error in previous patch.

Reviews?

Comment on attachment 74385 [details] [diff] [review] This is the fix This breaks compilation in layout/xul/base/src make: Entering directory `/local/nogin/rpmBUILD/mozilla/layout/xul/base/src' nsBoxObject.cpp c++ -o nsBoxObject.o -c -DOSTYPE=\"Linux2.4\" -DOSARCH=\"Linux\" -DOJI -D_IMPL_NS_HTML -I. -I./../../../base/src -I./../../../html/style/src -I./../../../html/base/src -I./../../../html/forms/src -I./../../content/src -I./../../../xml/content/src -I./../../../base/public -I../../../../dist/include/xpcom -I../../../../dist/include/string -I../../../../dist/include/dom -I../../../../dist/include/locale -I../../../../dist/include/content -I../../../../dist/include/gfx -I../../../../dist/include/widget -I../../../../dist/include/view -I../../../../dist/include/docshell -I../../../../dist/include/necko -I../../../../dist/include/editor -I../../../../dist/include/htmlparser -I../../../../dist/include/webshell -I../../../../dist/include/pref -I../../../../dist/include/intl -I../../../../dist/include/gfx2 -I../../../../dist/include/imglib2 -I../../../../dist/include/unicharutil -I../../../../dist/include/webbrwsr -I../../../../dist/include/xpconnect -I../../../../dist/include/js -I../../../../dist/include/layout -I../../../../dist/include -I/usr/u/nogin/rpmsrc/BUILD.nuprl3/mozilla/dist/include/nspr -I/usr/X11R6/include -fPIC -I/usr/X11R6/include -fno-rtti -fno-exceptions -Wall -Wconversion -Wpointer-arith -Wbad-function-cast -Wcast-align -Woverloaded-virtual -Wsynth -Wno-ctor-dtor-privacy -pedantic -Wno-long-long -fshort-wchar -pthread -pipe -DNDEBUG -DTRIMMED -O -I/usr/X11R6/include -DMOZILLA_CLIENT -include ../../../../config-defs.h -Wp,-MD,.deps/nsBoxObject.pp nsBoxObject.cpp nsBoxObject.cpp: In method `nsresult nsBoxObject::QueryInterface (const nsIID &, void **)': nsBoxObject.cpp:72: no matching function for call to `nsCOMPtr<nsIDOMScriptObjectFactory>::nsCOMPtr (const nsGetServiceByCID, nsresult *)' ../../../../dist/include/xpcom/nsCOMPtr.h:514: candidates are: nsCOMPtr<T>::nsCOMPtr () [with T = nsIDOMScriptObjectFactory] ../../../../dist/include/xpcom/nsCOMPtr.h:521: nsCOMPtr<T>::nsCOMPtr (const nsCOMPtr<T> &) [with T = nsIDOMScriptObjectFactory] ../../../../dist/include/xpcom/nsCOMPtr.h:530: nsCOMPtr<T>::nsCOMPtr (T *) [with T = nsIDOMScriptObjectFactory] ../../../../dist/include/xpcom/nsCOMPtr.h:540: nsCOMPtr<T>::nsCOMPtr (const already_AddRefed<T> &) [with T = nsIDOMScriptObjectFactory] ../../../../dist/include/xpcom/nsCOMPtr.h:548: nsCOMPtr<T>::nsCOMPtr (const nsCOMPtr_helper &) [with T = nsIDOMScriptObjectFactory] make: *** [nsBoxObject.o] Error 1 make: Leaving directory `/local/nogin/rpmBUILD/mozilla/layout/xul/base/src'

Attachment attachment 74428 [details] [diff] [review] indeed fixes some of the warnings. It still leaves one of the warnings though: nsSchemaLoader.cpp: In method `nsresult nsSchemaLoader::ProcessFacet (nsSchema *, nsIDOMElement *, nsIAtom *, nsISchemaFacet **)': nsSchemaLoader.cpp:2672: warning: `PRUint16 facetType' might be used uninitialized in this function

I filed bug 131347 on that because I don't know what the default value should be.

Comment on attachment 74428 [details] [diff] [review] Ba-ad day! I swear this is the one r=peterv

Comment on attachment 74428 [details] [diff] [review] Ba-ad day! I swear this is the one >+ nsresult rv; \ >+ nsCOMPtr<nsIDOMScriptObjectFactory> sof(do_GetService(kDOMSOF_CID, &rv));\ Split this (and the other one too) line into two lines after the comma so that the rhs of the macro lines up nicely. Other than that, sr=jst

Will do, I have that fixed in my tree. Sending for approval...

Comment on attachment 74428 [details] [diff] [review] Ba-ad day! I swear this is the one a=asa (on behalf of drivers) for checkin to the 1.0 trunk

Checked in.

Verifying, currently (http://tinderbox.mozilla.org/SeaMonkey/warn1016552220.1515.html - Tue, 19 Mar 2002 10:37 EST) the only "xxx might be used uninitialized" warning in xmlextras is the nsSchemaLoader.cpp one that is covered in a separate bug 127490.