spec: mangle /usr/bin/python shebangs to /usr/bin/python3

- From Fedora spec file
- Only for dom0 >= Fedora 31

kernel.spec.in

@@ -150,6 +150,27 @@ cd linux-%upstream_version
 # drop EXTRAVERSION - possible -rc suffix already included in %release
 sed -i -e 's/^EXTRAVERSION = -rc.*/EXTRAVERSION =/' Makefile
 
+%if 0%{?fedora} >= 31
+# Mangle /usr/bin/python shebangs to /usr/bin/python3
+# Mangle all Python shebangs to be Python 3 explicitly
+# -p preserves timestamps
+# -n prevents creating ~backup files
+# -i specifies the interpreter for the shebang
+# This fixes errors such as
+# *** ERROR: ambiguous python shebang in /usr/bin/kvm_stat: #!/usr/bin/python. Change it to python3 (or python2) explicitly.
+# We patch all sources below for which we got a report/error.
+pathfix.py -i "%{__python3} %{py3_shbang_opts}" -p -n \
+	tools/kvm/kvm_stat/kvm_stat \
+	scripts/show_delta \
+	scripts/diffconfig \
+	scripts/bloat-o-meter \
+	tools/perf/tests/attr.py \
+	tools/perf/scripts/python/stat-cpi.py \
+	tools/perf/scripts/python/sched-migration.py \
+	Documentation \
+	scripts/gen_compile_commands.py
+%endif
+
 cd %kernel_build_dir
 
 # Create QubesOS config kernel
@@ -266,6 +287,11 @@ fi
 
 rm -rf %buildroot/lib/modules/%kernelrelease/build/Documentation
 
+# Remove useless scripts that creates ERROR with ambiguous shebang
+# that are removed too in Fedora
+rm -rf %buildroot/lib/modules/%kernelrelease/build/scripts/tracing
+rm -f %buildroot/lib/modules/%kernelrelease/build/scripts/spdxcheck.py
+
 # disable GCC plugins for external modules build, to not fail if different gcc
 # version is used
 sed -e 's/^\(CONFIG_GCC_PLUGIN.*\)=y/# \1 is not set/' .config > \