android-clang mkspec broken in 5.9

git clone https://github.com/qt/qt5
cd qt5
git checkout 5.9
git submodule update --init qtbase qtdeclarative qtandroidextras qtdoc qtmultimedia qtimageformats qtquickcontrols qtquickcontrols2 qtrepotools qttools qtwebsockets
cd ../
mkdir build
cd build

../qt5/configure -opensource -confirm-license -xplatform android-clang -nomake tests -nomake examples -android-ndk /opt/android-ndk -android-sdk /opt/android-sdk -android-arch armeabi-v7a -no-warnings-are-errors -prefix /opt/qt-android

Preparing build tree...
<srcbase> = /opt/qt5/qtbase 
<outbase> = /opt/build/qtbase 
Creating qmake...
# I removed the qmake build lines since they are not very useful
.Done.
Info: creating stash file /opt/build/.qmake.stash
/opt/qt5/qtbase/mkspecs/features/toolchain.prf:129: Variable QMAKE_CXX.COMPILER_MACROS is not defined.

This is the Qt Open Source Edition.

You have already accepted the terms of the Open Source license.

Running configuration tests...
Checking for gold linker... no
Checking for valid makespec... Note: Also available for Linux: linux-clang linux-kcc linux-icc linux-cxx

ERROR: Cannot compile a minimal program. The toolchain or QMakeSpec is broken.

Command line: -opensource -confirm-license -xplatform android-clang -nomake tests -nomake examples -android-ndk /opt/android-ndk -android-sdk /opt/android-sdk -android-arch armeabi-v7a -no-warnings-are-errors -prefix /opt/qt-android
executing config test use_gold_linker
+ cd /opt/build/qtbase/config.tests && /opt/android-ndk/toolchains/llvm/prebuilt/linux-x86_64/bin/clang++ -fuse-ld=gold -o conftest-out conftest.cpp
> sh: /opt/android-ndk/toolchains/llvm/prebuilt/linux-x86_64/bin/clang++: Aucun fichier ou dossier de ce type
test config.qtbase.tests.use_gold_linker FAILED
executing config test verifyspec
+ cd /opt/build/qtbase/config.tests/common/verifyspec && /opt/build/qtbase/bin/qmake "CONFIG -= qt debug_and_release app_bundle lib_bundle" "CONFIG += shared console single_arch" -early "CONFIG += cross_compile" /opt/qt5/qtbase/config.tests/common/verifyspec
> /opt/qt5/qtbase/mkspecs/features/toolchain.prf:129: Variable QMAKE_CXX.COMPILER_MACROS is not defined.
+ cd /opt/build/qtbase/config.tests/common/verifyspec && MAKEFLAGS= /usr/bin/make
> /opt/android-ndk/toolchains/llvm/prebuilt/linux-x86_64/bin/clang++ -c -target armv7-none-linux-androideabi -fstack-protector-strong -DANDROID -march=armv7-a -mfloat-abi=softfp -mfpu=vfp -fno-builtin-memmove --sysroot=/opt/android-ndk/platforms/android-16/arch-arm/ -O2 -Os -mthumb -std=gnu++11 -Wall -W -fPIC  -I/opt/qt5/qtbase/config.tests/common/verifyspec -I. -isystem /opt/android-ndk/sources/cxx-stl/gnu-libstdc++/4.9/include -isystem /opt/android-ndk/sources/cxx-stl/gnu-libstdc++/4.9/libs/armeabi-v7a/include -isystem /opt/android-ndk/platforms/android-16/arch-arm/usr/include -I/opt/qt5/qtbase/mkspecs/android-clang -o verifyspec.o /opt/qt5/qtbase/config.tests/common/verifyspec/verifyspec.cpp
> make: /opt/android-ndk/toolchains/llvm/prebuilt/linux-x86_64/bin/clang++: Command not found
> make: *** [Makefile:178: verifyspec.o] Error 127