As of this afternoon, g++ hangs while compiling nsStyleContext.cpp in the Mozilla tree with -O2. I'll attach the preprocessed output to make for easy testing. Given nsStyleContext.ii that I will attach, the command c++ -c -o nsStyleContext.o -O2 nsStyleContext.ii hangs, while the command c++ -c -o nsStyleContext.o nsStyleContext.ii works correctly. I'm seeing this with gcc-2.96-70 and -O2. tor reports the same problem with gcc-2.96-74 and -O (rather than -O2). mao reports it with gcc-2.96-69.
Created attachment 10440 [details] nsStyleContext.ii - preprocessed source
Thanks. Actually, CVS head hangs on this as well. The culprit is: inline void CalcSidesFor(const nsIFrame* aFrame, const nsStyleSides& aSides, PRUint8 aSpacing, const nscoord* aEnumTable, PRInt32 aNumEnums, nsMargin& aResult) { nsStyleCoord coord; aResult.left = CalcSideFor(aFrame, aSides.GetLeft(coord), aSpacing, 3, aEnumTable, aNumEnums); aResult.top = CalcSideFor(aFrame, aSides.GetTop(coord), aSpacing, 0, aEnumTable, aNumEnums); aResult.right = CalcSideFor(aFrame, aSides.GetRight(coord), aSpacing, 1, aEnumTable, aNumEnums); aResult.bottom = CalcSideFor(aFrame, aSides.GetBottom(coord), aSpacing, 2, aEnumTable, aNumEnums); } and the tree based inlining for some reason does not limit itself in doing further and further inlines of itself in this case (because CalcSideFor indirectly calls CalcSidesFor). I'll try to simplify it first.
With -O (not O3) and with gcc-2.96-54, it takes a long time, and finally gives up with: Cannot allocate 892625676 bytes after allocating 16260924 bytes
I've narrowed it down to a 3K testcase and it really does not hang, it just does a lot of inlining and eats gobs of memory (if I remove one of the 4 routines for inlining, it actually succeeds on my 256MB box, otherwise I never had the patience to let it finish). I hope I'll know more tomorrow.
Any movement on this? It's a real killer.
Yes, I think I've fixed this by: http://gcc.gnu.org/ml/gcc-patches/2001-02/msg01310.html Mark Mitchell approved it, if Jason Merrill does not have anything against it until tomorrow, I'll commit it and will include it into gcc-c++-2.96-76.
Are you committing the patch to both the gcc trunk and the gcc 3.0 branch? I sure hope this is fixed in gcc 3.0 also.
Sure, I've commited it to both branch and head.
*** Bug 31937 has been marked as a duplicate of this bug. ***