--- a/vulkan.spec
+++ b/vulkan.spec
@@ -15,6 +15,7 @@ Source1: vulkan-headers.tar
 Source2: vulkan-tools.tar
 # https://github.com/KhronosGroup/Vulkan-ValidationLayers
 Source3: vulkan-layers.tar
+Patch1: alt-pthreads.patch
 
 BuildRequires: bison chrpath
 BuildRequires(pre): cmake gcc-c++ rpm-build-python3
@@ -101,6 +102,7 @@ verify their applications correct use of the Vulkan API.
 %prep
 %setup -n %name-loader -b0 -b1 -b2 -b3
 pushd ../vulkan-layers
+%patch1 -p1
 # sigh inttypes
 sed -i 's/inttypes.h/cinttypes/' layers/*.{cpp,h}
 popd