qtdeclarative/src/qml/memory/qv4heap_p.h:55:10: fatal error: ./private/qv4mmdefs_p.h: Invalid argument

Qt5.git integration fails in '5.12':

agent:2020/05/25 07:35:15 build.go:253: In file included from ..\..\include\QtQml\5.12.9\QtQml/private/qv4heap_p.h:1:0,
agent:2020/05/25 07:35:15 build.go:253: from C:/Users/qt/work/qt/qtdeclarative/src/qml/jsruntime/qv4value_p.h:58,
agent:2020/05/25 07:35:15 build.go:253: from C:/Users/qt/work/qt/qtdeclarative/src/qml/jsruntime/qv4managed_p.h:54,
agent:2020/05/25 07:35:15 build.go:253: from C:/Users/qt/work/qt/qtdeclarative/src/qml/jsruntime/qv4string_p.h:54,
agent:2020/05/25 07:35:15 build.go:253: from ..\..\include\QtQml\5.12.9\QtQml/private/qv4string_p.h:1,
agent:2020/05/25 07:35:15 build.go:253: from C:/Users/qt/work/qt/qtdeclarative/src/qml/qml/ftw/qhashedstring_p.h:56,
agent:2020/05/25 07:35:15 build.go:253: from ..\..\include\QtQml\5.12.9\QtQml/private/qhashedstring_p.h:1,
agent:2020/05/25 07:35:15 build.go:253: from C:/Users/qt/work/qt/qtdeclarative/src/qml/qml/qqmltypeloader_p.h:67,
agent:2020/05/25 07:35:15 build.go:253: from C:/Users/qt/work/qt/qtdeclarative/src/qml/qml/qqmlengine_p.h:56,
agent:2020/05/25 07:35:15 build.go:253: from ..\..\include\QtQml\5.12.9\QtQml/private/qqmlengine_p.h:1,
agent:2020/05/25 07:35:15 build.go:253: from qml\qqmlvme_p.h:64,
agent:2020/05/25 07:35:15 build.go:253: from qml\qqmlvme.cpp:40:
agent:2020/05/25 07:35:15 build.go:253: C:/Users/qt/work/qt/qtdeclarative/src/qml/memory/qv4heap_p.h:55:10: fatal error: ./private/qv4mmdefs_p.h: Invalid argument
agent:2020/05/25 07:35:15 build.go:253: #include <private/qv4mmdefs_p.h>
agent:2020/05/25 07:35:15 build.go:253: ^~~~~~~~~~~~~~~~~~~~~~~
agent:2020/05/25 07:35:15 build.go:253: compilation terminated.
agent:2020/05/25 07:35:15 build.go:253: Mingw32-make[3]: *** [Makefile.Debug:35778: .obj/debug/qqmlvme.o] Error 1

Log: https://testresults.qt.io/coin/api/results/qt/qtdeclarative/7aae8a39e9612f0f6376ea4da70f13050874c0b0/WindowsWindows_7x86WindowsWindows_7x86Mingw73qtci-windows-7-x86-3-c52e87DisableTests/e3a510c228e3c1a07565e1156f580ef6c94e2976/build_1590388217/log.txt.gz

Details: https://testresults.qt.io/coin/integration/qt/qt5/tasks/1590388007