#12965: String merging broken on Windows ---------------------------------+---------------------------------------- Reporter: bgamari | Owner: (none) Type: bug | Status: upstream Priority: normal | Milestone: 8.8.1 Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Operating System: Windows | Architecture: Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D3384 Wiki Page: | ---------------------------------+---------------------------------------- Comment (by Phyx-): The specific implementation in GCC/binutils won't work for non-ELF targets it turns out. However I have an implementation that should do this using a similar method as the D compiler uses by leveraging ld's `.gnu.linkonce` support for PE targets. This method however needs a guarantee from the compiler that it doesn't output duplicate string constants, or GAS will end up merging them and breaking the approach. (This is what was going wrong in the Diff as WIP on Phab). It seems that GHC doesn't do this at the moment, it only happens to have this effect some of the them due to CSEing. So I have written a new string constant pooling pass that does this. In order to make it lightweight I changed the syntax to allow multiple labels at definition site. Such that I don't have to actually change the usage sites. I've changed all the back-ends but have a bug to fix and still need to figure out how to test the llvm, macos and unregister changes. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12965#comment:12 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler