Here's the output: DerivedSources/WebCore/MathMLNames.cpp:641:66: error: 'Steral' has not been declared StringImpl::StaticASCIILiteral::s_initialFlags | (8634190 << Steral::s_hashShift) ^ DerivedSources/WebCore/MathMLNames.cpp:643:39: error: redefinition of 'WTF::StringImpl::StaticASCIILiteral WebCore::MathMLNames::mathbackgroundData' static StringImpl::StaticASCIILiteral mathbackgroundData = { ^ DerivedSources/WebCore/MathMLNames.cpp:216:39: error: 'WTF::StringImpl::StaticASCIILiteral WebCore::MathMLNames::mathbackgroundData' previously defined here static StringImpl::StaticASCIILiteral mathbackgroundData = { ^ DerivedSources/WebCore/MathMLNames.cpp: In function 'void WebCore::MathMLNames::init()': DerivedSources/WebCore/MathMLNames.cpp:932:58: error: 'miData' was not declared in this scope { (void*)&miTag, *reinterpret_cast<StringImpl*>(&miData) }, ^ make[2]: *** [DerivedSources/WebCore/libWebCore_la-MathMLNames.lo] Error 1 make[2]: *** Waiting for unfinished jobs....
Hmm... I regenerated MathMLNames.cpp and now it builds fine, I wonder what happened here. Two generator scripts running in parallel maybe?
I haven't seen this problem again and I've been able to build this release in several machines with different architectures, so I assume there was something wrong in my environment.