Create absolute symlink for test executableswip/T20208

This is necessary because the symlink needs to be created between two
arbritary filepaths in the build tree, it's hard to compute how to get
between them relatively. As this symlink doesn't end up in a bindist
then it's fine for it to be absolute.

1 files changed, 3 insertions, 1 deletions

diff --git a/hadrian/src/Rules/Test.hs b/hadrian/src/Rules/Test.hs
index ff986f879e..eeddfd9c3b 100644
--- a/hadrian/src/Rules/Test.hs
+++ b/hadrian/src/Rules/Test.hs
@@ -18,6 +18,7 @@ import Settings.Program (programContext)
 import Target
 import Utilities
 import Context.Type
+import qualified System.Directory as IO
 
 ghcConfigHsPath :: FilePath
 ghcConfigHsPath = "testsuite/mk/ghc-config.hs"
@@ -81,7 +82,8 @@ testRules = do
               then do
                 let stg = stageOf testGhc
                 prog_path <- programPath =<< programContext stg progPkg
-                createFileLink prog_path path
+                abs_prog_path <- liftIO (IO.canonicalizePath prog_path)
+                createFileLink abs_prog_path path
             -- otherwise, build it by directly invoking ghc
               else do
                 bindir <- getBinaryDirectory testGhc