Merge pull request dotnet#22232 from nguerrera/fix-doc-xml-build-race

Fix build parallelism issue with documentation file generation
ViktorHofer · Sep 25, 2017 · 49f9176 · 49f9176
2 parents c1e62d1 + fddce6c
commit 49f9176
Showing 1 changed file with 8 additions and 3 deletions.
diff --git a/build/Targets/Imports.targets b/build/Targets/Imports.targets
@@ -48,11 +48,16 @@
 
   <!-- 
     DocumentationFile needs to be set before importing common targets. 
-    C# common targets (unlike VB) prefix DocumentationFile path with IntermediateOutputPath.
+
+    C# common targets (unlike VB) prefix DocumentationFile path with IntermediateOutputPath. However, using that here does not work with multi-targeting as
+    the IntermediateOutputPath will not yet have the TargetFramework appended, which will lead to a race where parallel builds for different TargetFrameworks
+    attempt to write the doc xml to the same xml location. Instead, we can simply set GenerateDocumentationFile=true and let the SDK pick the correct path.
+
+    Ideally, we'd just use the same construct for VB here, but that is currently blocked by https://github.com/dotnet/sdk/issues/1598.
   -->
-  <PropertyGroup Condition="'$(DocumentationFile)' == '' AND '$(NoDocumentationFile)' != 'true' AND '$(AssemblyName)' != ''">
+  <PropertyGroup Condition="'$(GenerateDocumentationFile)' == '' AND '$(DocumentationFile)' == '' AND '$(NoDocumentationFile)' != 'true' AND '$(AssemblyName)' != ''">
     <DocumentationFile Condition="'$(ProjectLanguage)' == 'VB'">$(AssemblyName).xml</DocumentationFile>
-    <DocumentationFile Condition="'$(ProjectLanguage)' == 'CSharp'">$(IntermediateOutputPath)\$(AssemblyName).xml</DocumentationFile>
+    <GenerateDocumentationFile Condition="'$(ProjectLanguage)' == 'CSharp'">true</GenerateDocumentationFile>
   </PropertyGroup>
 
   <PropertyGroup>