dkms - check for clang compiler

gistfile1.txt

--- a/usr/bin/dkms	2020-12-11 09:54:28.000000000 +0100
+++ b/usr/bin/dkms	2021-07-13 11:51:05.517800608 +0200
@@ -1284,6 +1284,17 @@
     cd - >/dev/null
 }
 
+check_clang()
+{
+    set_kernel_source_dir "$kernelver"
+    if [[ ! -z $(strings ${kernel_source_dir}/vmlinux | grep clang) ]] ; then
+        _clangopts="CC=clang LD=ld.lld AR=llvm-ar NM=llvm-nm RANLIB=llvm-ranlib STRIP=llvm-strip OBJCOPY=llvm-objcopy"
+        echo "Using llvm tools..."
+    else
+        _clangopts=""
+    fi
+}
+
 # Get ready to build a module that has been registered with DKMS.
 prepare_build()
 {
@@ -1293,6 +1304,9 @@
     set_kernel_source_dir "$kernelver"
     local base_dir="$dkms_tree/$module/$module_version/$kernelver/$arch"
 
+    # check if the kernel was compiled with clang
+    check_clang
+    
     # Check that the right arguments were passed
     check_module_args build
 
@@ -1350,7 +1364,7 @@
     invoke_command "$clean" "cleaning build area" background
     echo $"DKMS make.log for $module-$module_version for kernel $kernelver ($arch)" >> "$dkms_tree/$module/$module_version/build/make.log"
     date >> "$dkms_tree/$module/$module_version/build/make.log"
-    local the_make_command="${make_command/#make/make -j$parallel_jobs KERNELRELEASE=$kernelver}"
+    local the_make_command="${make_command/#make/make -j$parallel_jobs KERNELRELEASE=$kernelver $_clangopts}"
 
     invoke_command "{ $the_make_command; } >> $dkms_tree/$module/$module_version/build/make.log 2>&1" "$the_make_command" background || \
         report_build_problem 10 $"Bad return status for module build on kernel: $kernelver ($arch)" \