qmake puts pkgconfig include pathes before local ones, so during a qt build it will often happen that the path where pcre.h is on a normal system is included in the pkgconfig path (for me /usr/local/include) and so the unicode safe pcre.h that is in tree is ignored. This should/could be remedied by renaming the header in tree.
Files with the same name inside the source tree should win over "system" header files. Renaming the file would likely resolve the problem, but the more correct fix would be to have the build system pass the correct include paths to the compiler.
zackr tells me this is probably a qmake issue which doesn't present in his system, so he can't really fix it. Though I agree the problem should be fixed in qmake I'm at a loss as to what that'd take.
Only reference to PCRE, I can find within C++ code on Webkit Github repo was this line in comment: https://github.com/WebKit/WebKit/blob/c9fb599a37ed367b3daece9eac1c461ef142b267/Source/JavaScriptCore/yarr/YarrParser.h#L1222 I think PCRE remnants have been removed and I think we can close this bug? Thanks!
Yes, we have an entirely different regex implementation now.