Compiler and linker open some source files with exclusive access

[wixbot]

The compiler and linker open some source files with exclusive access instead of read-share access. This causes intermittent problems when performing multi-core builds. Any files that are only being read should be opened with read-share access so that multiple threads / processes can read the file simultaneously.

Originally opened by thomas.hammond

[wixbot]

Please be more specific. Which source files? Which tools? Source files in the compiler are opened with read sharing. Have you looked at anti-virus interference?

[wixbot]

I think it was coming from the linker when it was reading an ICO file to use as the package icon. After taking a closer look at the 3.8 code, it looks like there is only once place where this is happening (I thought there were more, but I was wrong), and it is stinging us randomly. Here is the offending line:

File: src\DTF\Libraries\Resources\GroupIconResource.cs: ~line 95 (ReadFromFile method)
-> using (FileStream fs = File.Open(path, FileMode.Open, FileAccess.Read))

The default FileShare mode is None, so if one thread is reading the icon, no other threads can also open it for read. I think this needs to be changed so that other threads can read the file:
-> using (FileStream fs = File.Open(path, FileMode.Open, FileAccess.Read, FileShare.Read))

Or it could just be changed to use File.OpenRead, which automatically uses FileShare.Read under the covers. This is what is done in many places for Wix read operations.

Originally posted by thomas.hammond

[wixbot]

Thanks for narrowing it down!

Originally posted by barnson
Status changed from Open to Untriaged

[wixbot]

Area changed from compiler to sdk
AssignedTo set to bobarnson
Release changed from v3.8 to v3.9

[wixbot]

Originally changed by barnson
Resolution set to fixed
Status changed from Open to Resolved