[project @ 2001-10-16 15:14:41 by simonpj]

[ghc-hetmet.git] / ghc / compiler / main / DriverPipeline.hs

diff --git a/ghc/compiler/main/DriverPipeline.hs b/ghc/compiler/main/DriverPipeline.hs
index 0db9de7..92f22d0 100644 (file)
--- a/ghc/compiler/main/DriverPipeline.hs
+++ b/ghc/compiler/main/DriverPipeline.hs
@@ -374,7 +374,15 @@ run_phase Cpp basename suff input_fn output_fn
                            ++ map SysTools.Option md_c_flags
                            ++ [ SysTools.Option     "-x"
                               , SysTools.Option     "c"
-                              , SysTools.FileOption "" input_fn
+                              , SysTools.Option     input_fn
+       -- We hackily use Option instead of FileOption here, so that the file
+       -- name is not back-slashed on Windows.  cpp is capable of
+       -- dealing with / in filenames, so it works fine.  Furthermore
+       -- if we put in backslashes, cpp outputs #line directives
+       -- with *double* backslashes.   And that in turn means that
+       -- our error messages get double backslashes in them.
+       -- In due course we should arrange that the lexer deals
+       -- with these \\ escapes properly.
                               , SysTools.Option     "-o"
                               , SysTools.FileOption "" output_fn
                               ])