I was using the QT Creator with an old GCC, now i updated to the 4.8 version. But the QT Creator adds a -Xarch_x86_64 option, the GCC 4.8 tells me
g++: error
I removed all the references using.
QMAKE_CFLAGS_PPC_64 -= -arch ppc64 -Xarch_ppc64 -mmacosx-version-min=10.5
QMAKE_OBJECTIVE_CFLAGS_PPC_64 -= -arch ppc64 -Xarch_ppc64 -mmacosx-version-min=10.5
QMAKE_CFLAGS_X86_64 -= -arch x86_64 -Xarch_x86_64 -mmacosx-version-min=10.5
QMAKE_OBJECTIVE_CFLAGS_X86_64 -= -arch x86_64 -Xarch_x86_64 -mmacosx-version-min=10.5
QMAKE_CXXFLAGS_PPC_64 -= -arch ppc64 -Xarch_ppc64 -mmacosx-version-min=10.5
QMAKE_CXXFLAGS_X86_64 -= -arch x86_64 -Xarch_x86_64 -mmacosx-version-min=10.5
QMAKE_LFLAGS_PPC_64 -= -arch ppc64 -Xarch_ppc64 -mmacosx-version-min=10.5
QMAKE_LFLAGS_X86_64 -= -arch x86_64 -Xarch_x86_64 -mmacosx-version-min=10.5
It solved my problem