bug#34062: qtwebkit-5.212.0-alpha2 parallel build failure

[Ludovic Courtès]

Seen on berlin:

--8<---------------cut here---------------start------------->8---
[ 81%] Generating 
../../DerivedSources/WebKit2/NPObjectMessageReceiverMessageReceiver.cpp, 
../../DerivedSources/WebKit2/NPObjectMessageReceiverMessages.h
cd 
/tmp/guix-build-qtwebkit-5.212.0-alpha2.drv-0/qtwebkit-5.212.0-alpha2/Source/WebKit2
 && /gnu/store/g87hamjyipk1j6dfq5pjfzfnfb64spbv-python2-2.7.15/bin/python2.7 
/tmp/g
uix-build-qtwebkit-5.212.0-alpha2.drv-0/qtwebkit-5.212.0-alpha2/Source/WebKit2/Scripts/generate-message-receiver.py
 Shared/Plugins/NPObjectMessageReceiver.messages.in > /
tmp/guix-build-qtwebkit-5.212.0-alpha2.drv-0/build/DerivedSources/WebKit2/NPObjectMessageReceiverMessageReceiver.cpp
[ 81%] Generating 
../../DerivedSources/WebKit2/DrawingAreaProxyMessageReceiver.cpp, 
../../DerivedSources/WebKit2/DrawingAreaProxyMessages.h
[ 81%] Generating 
../../DerivedSources/WebKit2/VisitedLinkStoreMessageReceiver.cpp, 
../../DerivedSources/WebKit2/VisitedLinkStoreMessages.h
[ 81%] Generating 
../../DerivedSources/WebKit2/WebBatteryManagerProxyMessageReceiver.cpp, 
../../DerivedSources/WebKit2/WebBatteryManagerProxyMessages.h
cd 
/tmp/guix-build-qtwebkit-5.212.0-alpha2.drv-0/qtwebkit-5.212.0-alpha2/Source/WebKit2
 && /gnu/store/g87hamjyipk1j6dfq5pjfzfnfb64spbv-python2-2.7.15/bin/python2.7 
/tmp/g
uix-build-qtwebkit-5.212.0-alpha2.drv-0/qtwebkit-5.212.0-alpha2/Source/WebKit2/Scripts/generate-message-receiver.py
 UIProcess/DrawingAreaProxy.messages.in > /tmp/guix-bui
ld-qtwebkit-5.212.0-alpha2.drv-0/build/DerivedSources/WebKit2/DrawingAreaProxyMessageReceiver.cpp
cd 
/tmp/guix-build-qtwebkit-5.212.0-alpha2.drv-0/qtwebkit-5.212.0-alpha2/Source/WebKit2
 && /gnu/store/g87hamjyipk1j6dfq5pjfzfnfb64spbv-python2-2.7.15/bin/python2.7 
/tmp/g
uix-build-qtwebkit-5.212.0-alpha2.drv-0/qtwebkit-5.212.0-alpha2/Source/WebKit2/Scripts/generate-message-receiver.py
 UIProcess/VisitedLinkStore.messages.in > /tmp/guix-bui
ld-qtwebkit-5.212.0-alpha2.drv-0/build/DerivedSources/WebKit2/VisitedLinkStoreMessageReceiver.cpp
cd 
/tmp/guix-build-qtwebkit-5.212.0-alpha2.drv-0/qtwebkit-5.212.0-alpha2/Source/WebKit2
 && /gnu/store/g87hamjyipk1j6dfq5pjfzfnfb64spbv-python2-2.7.15/bin/python2.7 
/tmp/g
uix-build-qtwebkit-5.212.0-alpha2.drv-0/qtwebkit-5.212.0-alpha2/Source/WebKit2/Scripts/generate-message-receiver.py
 UIProcess/WebBatteryManagerProxy.messages.in > /tmp/gu
ix-build-qtwebkit-5.212.0-alpha2.drv-0/build/DerivedSources/WebKit2/WebBatteryManagerProxyMessageReceiver.cpp
[ 81%] Generating 
../../DerivedSources/WebKit2/WebCookieManagerProxyMessageReceiver.cpp, 
../../DerivedSources/WebKit2/WebCookieManagerProxyMessages.h
cd 
/tmp/guix-build-qtwebkit-5.212.0-alpha2.drv-0/qtwebkit-5.212.0-alpha2/Source/WebKit2
 && /gnu/store/g87hamjyipk1j6dfq5pjfzfnfb64spbv-python2-2.7.15/bin/python2.7 
/tmp/g
uix-build-qtwebkit-5.212.0-alpha2.drv-0/qtwebkit-5.212.0-alpha2/Source/WebKit2/Scripts/generate-message-receiver.py
 UIProcess/WebCookieManagerProxy.messages.in > /tmp/gui
x-build-qtwebkit-5.212.0-alpha2.drv-0/build/DerivedSources/WebKit2/WebCookieManagerProxyMessageReceiver.cpp
[ 81%] Generating 
../../DerivedSources/WebKit2/WebFullScreenManagerProxyMessageReceiver.cpp, 
../../DerivedSources/WebKit2/WebFullScreenManagerProxyMessages.h
cd 
/tmp/guix-build-qtwebkit-5.212.0-alpha2.drv-0/qtwebkit-5.212.0-alpha2/Source/WebKit2
 && /gnu/store/g87hamjyipk1j6dfq5pjfzfnfb64spbv-python2-2.7.15/bin/python2.7 
/tmp/g
uix-build-qtwebkit-5.212.0-alpha2.drv-0/qtwebkit-5.212.0-alpha2/Source/WebKit2/Scripts/generate-message-receiver.py
 UIProcess/WebFullScreenManagerProxy.messages.in > /tmp
/guix-build-qtwebkit-5.212.0-alpha2.drv-0/build/DerivedSources/WebKit2/WebFullScreenManagerProxyMessageReceiver.cpp
Traceback (most recent call last):
  File 
"/tmp/guix-build-qtwebkit-5.212.0-alpha2.drv-0/qtwebkit-5.212.0-alpha2/Source/WebKit2/Scripts/generate-message-receiver.py",
 line 28, in <module>
    import webkit.messages
ValueError: bad marshal data (string size out of range)
[ 81%] Generating 
../../DerivedSources/WebKit2/WebGeolocationManagerProxyMessageReceiver.cpp, 
../../DerivedSources/WebKit2/WebGeolocationManagerProxyMessages.h
cd 
/tmp/guix-build-qtwebkit-5.212.0-alpha2.drv-0/qtwebkit-5.212.0-alpha2/Source/WebKit2
 && /gnu/store/g87hamjyipk1j6dfq5pjfzfnfb64spbv-python2-2.7.15/bin/python2.7 
/tmp/g
uix-build-qtwebkit-5.212.0-alpha2.drv-0/qtwebkit-5.212.0-alpha2/Source/WebKit2/Scripts/generate-message-receiver.py
 UIProcess/WebGeolocationManagerProxy.messages.in > 
/tmp/guix-build-qtwebkit-5.212.0-alpha2.drv-0/build/DerivedSources/WebKit2/WebGeolocationManagerProxyMessageReceiver.cpp
make[2]: *** [Source/WebKit2/CMakeFiles/WebKit2.dir/build.make:254: 
DerivedSources/WebKit2/VisitedLinkStoreMessageReceiver.cpp] Error 1
make[2]: *** Deleting file 
'DerivedSources/WebKit2/VisitedLinkStoreMessageReceiver.cpp'
--8<---------------cut here---------------end--------------->8---

Looks like a non-parallel-safe Makefile.

Ludo’.