Merge pull request #5319 from shuujii/check-if-.pi-build-rules-are-defined

Check if `.pi` build rules are defined

tasks/presym.rake

@@ -17,7 +17,7 @@ MRuby.each_target do |build|
   build.gems.each{|gem| gem.compilers.each{|c| c.include_paths << include_dir}}
 
   prereqs = {}
-  pps = []
+  ppps = []
   build_dir = "#{build.build_dir}/"
   mrbc_build_dir = "#{build.mrbc_build.build_dir}/" if build.mrbc_build
   build.products.each{|product| all_prerequisites.(product, prereqs)}
@@ -25,11 +25,15 @@ MRuby.each_target do |build|
     next unless File.extname(prereq) == build.exts.object
     next unless prereq.start_with?(build_dir)
     next if mrbc_build_dir && prereq.start_with?(mrbc_build_dir)
-    pps << prereq.ext(build.exts.presym_preprocessed)
+    ppp = prereq.ext(build.exts.presym_preprocessed)
+    if Rake.application.lookup(ppp) ||
+       Rake.application.enhance_with_matching_rule(ppp)
+      ppps << ppp
+    end
   end
 
-  file presym.list_path => pps do
-    presyms = presym.scan(pps)
+  file presym.list_path => ppps do
+    presyms = presym.scan(ppps)
     current_presyms = presym.read_list if File.exist?(presym.list_path)
     update = presyms != current_presyms
     presym.write_list(presyms) if update