diff --git a/lib/propshaft/compiler/source_mapping_urls.rb b/lib/propshaft/compiler/source_mapping_urls.rb
index 0a32d90..2cdb260 100644
--- a/lib/propshaft/compiler/source_mapping_urls.rb
+++ b/lib/propshaft/compiler/source_mapping_urls.rb
@@ -6,11 +6,14 @@ class Propshaft::Compiler::SourceMappingUrls < Propshaft::Compiler
   SOURCE_MAPPING_PATTERN = %r{(//|/\*)# sourceMappingURL=(.+\.map)(\s*?\*\/)?\s*?\Z}
 
   def compile(logical_path, input)
-    input.gsub(SOURCE_MAPPING_PATTERN) { source_mapping_url(asset_path($2, logical_path), $1, $3) }
+    @logical_path = logical_path
+    input.gsub(SOURCE_MAPPING_PATTERN) { source_mapping_url(asset_path($2), $1, $3) }
   end
 
   private
-    def asset_path(source_mapping_url, logical_path)
+    attr_reader :logical_path
+
+    def asset_path(source_mapping_url)
       if logical_path.dirname.to_s == "."
         source_mapping_url
       else
@@ -22,7 +25,7 @@ def source_mapping_url(resolved_path, comment_start, comment_end)
       if asset = assembly.load_path.find(resolved_path)
         "#{comment_start}# sourceMappingURL=#{url_prefix}/#{asset.digested_path}#{comment_end}"
       else
-        Propshaft.logger.warn "Removed sourceMappingURL comment for missing asset '#{resolved_path}' from #{resolved_path}"
+        Propshaft.logger.warn "Removed sourceMappingURL comment for missing asset '#{resolved_path}' from #{logical_path}"
         "#{comment_start}#{comment_end}"
       end
     end