Don't error out with -singleobj, -of, and -c/-output-{bc,ll,o,s}.

dmd/module.c

@@ -219,7 +219,7 @@ static void check_and_add_output_file(Module* NewMod, const std::string& str)
     files.insert(std::make_pair(str, NewMod));
 }
 
-void Module::buildTargetFiles()
+void Module::buildTargetFiles(bool singleObj)
 {
     if(objfile && 
        (!doDocComment || docfile) && 
@@ -252,7 +252,8 @@ void Module::buildTargetFiles()
 
     // LDC
     // another safety check to make sure we don't overwrite previous output files
-    check_and_add_output_file(this, objfile->name->str);
+    if (!singleObj)
+        check_and_add_output_file(this, objfile->name->str);
     if (docfile)
         check_and_add_output_file(this, docfile->name->str);
     if (hdrfile)

dmd/module.h

@@ -188,7 +188,7 @@ struct Module : Package
 #if IN_LLVM
     // LDC
     llvm::Module* genLLVMModule(llvm::LLVMContext& context, Ir* sir);
-    void buildTargetFiles();
+    void buildTargetFiles(bool singleObj);
     File* buildFilePath(const char* forcename, const char* path, const char* ext);
     Module *isModule() { return this; }
 

gen/main.cpp

@@ -781,7 +781,7 @@ LDC_TARGETS
         m->importedFrom = m;
         m->read(0);
         m->parse();
-        m->buildTargetFiles();
+        m->buildTargetFiles(singleObj);
         m->deleteObjFile();
         if (m->isDocFile)
         {