RESOLVED FIXED254757
SVGPathSegValue::clone<>() rename to SVGPathSegValue::cloneInternal<>() 
https://bugs.webkit.org/show_bug.cgi?id=254757
Summary SVGPathSegValue::clone<>() rename to SVGPathSegValue::cloneInternal<>()
Michael Catanzaro
Reported 2023-03-30 11:43:11 PDT
SVGPathSeg has a virtual function SVGPathSeg::clone which you would expect to clone any SVGPathSeg, retaining its derived type. However, the virtual clone gets hidden by SVGPathSegValue<PathSegType>::clone because templated functions are never virtual. I think this means a clone operation on a SVGPathSeg pointer will work correctly if the SVGPathSeg is a SVGPathSegValue. This problem was found by GCC 13's -Woverloaded-virtual warning. I don't know what to do about this. For now I'll just suppress the warning.
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Michael Catanzaro
Comment 1 2023-03-30 11:46:34 PDT
(In reply to Michael Catanzaro from comment #0) > I think this means a clone operation on a > SVGPathSeg pointer will work correctly if the SVGPathSeg is a > SVGPathSegValue. I meant: will not work correctly. The SVGPathSegValue<PathSegType>::clone would only get called via a pointer to an SVGPathSegValue<PathSegType>. With a pointer to an SVGPathSeg, I think the program should abort with a runtime error due to unimplemented virtual function?
Radar WebKit Bug Importer
Comment 2 2023-04-06 11:44:16 PDT
<rdar://problem/107719787>
Said Abou-Hallawa
Comment 3 2023-04-06 13:41:17 PDT
I think this might be a bug or limitation in GCC 13 complier. The clang complier considers the template function SVGPathSegValue::clone<>() different from the virtual function SVGPathSeg::clone() so it does not generate an error saying the template function hides the virtual implementations. Open LayoutTests/svg/dom/SVGPathSegList-insert-from-animating-animPathSegList.svg in the debugger and set a breakpoint in SVGPathSegMovetoAbs::clone(). In Xcode the debugger breaks at the function. SVGPathSegValue::clone<>() should be renamed to SVGPathSegValue::cloneInternal<>(). So the code can be complied on GCC 13 without the need for -Woverloaded-virtual.
Said Abou-Hallawa
Comment 4 2023-04-06 13:51:42 PDT
Pull request: https://github.com/WebKit/WebKit/pull/12476
EWS
Comment 5 2023-04-06 16:23:13 PDT
Committed 262690@main (9fc3aff2f387): <https://commits.webkit.org/262690@main> Reviewed commits have been landed. Closing PR #12476 and removing active labels.
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