[COFF] Check errorCount before committing the output file

mstorsjo · mstorsjo · commit 08a5a0aa252a · 2019-08-20T21:08:14.000Z
This avoids producing an output file if errors appeared late in the linking process (e.g. while fixing relocations, or as in the test, while checking for multiple resources). If an output file is produced, build tools might not retry building it on rebuilds, even if a previous build failed due to the error return code. Differential Revision: https://reviews.llvm.org/D66491 llvm-svn: 369445
diff --git a/lld/COFF/Writer.cpp b/lld/COFF/Writer.cpp
@@ -628,6 +628,9 @@ void Writer::run() {
 
   writeMapFile(outputSections);
 
+  if (errorCount())
+    return;
+
   ScopedTimer t2(diskCommitTimer);
   if (auto e = buffer->commit())
     fatal("failed to write the output file: " + toString(std::move(e)));
diff --git a/lld/test/COFF/multiple-resource-objs.test b/lld/test/COFF/multiple-resource-objs.test
@@ -1,7 +1,9 @@
 # RUN: llvm-cvtres /out:%t_resource.obj %S/Inputs/resource.res
 # RUN: llvm-cvtres /out:%t_id.obj %S/Inputs/id.res
+# RUN: rm -f %t.exe
 # RUN: not lld-link /out:%t.exe /dll /noentry %t_id.obj %t_resource.obj 2>&1 | \
 # RUN:     FileCheck --check-prefix=TWOOBJ %s
+# RUN: not test -f %t.exe
 
 TWOOBJ: error: {{.*}}_resource.obj: more than one resource obj file not allowed, already got {{.*}}_id.obj
 
