[commit: ghc] master: configure.ac: Ensure that we handle case of non-present --target (b09bf4b)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/b09bf4b0c0b01c1c53e972e52ceaeb28de66ae07/ghc

>---------------------------------------------------------------

commit b09bf4b0c0b01c1c53e972e52ceaeb28de66ae07
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Thu Mar 9 16:19:56 2017 -0500

    configure.ac: Ensure that we handle case of non-present --target
    
    @rwbarton pointed out that this could be an issue during review, but I
    assumed from my point sample of three test builds that this wouldn't be
    necessary.  Sadly, none of these builds were on Windows, which indeed
    does fail.
    
    Strangely, only Simon and Harbormaster have been able to replicate the
    issue (which apparently manifests as libffi thinking it's building for
    unix).  I've been completely unable to replicate the failure in my own
    builds, neither locally nor on the Harbormaster machine.
    
    Test Plan: Validate on Windows
    
    Reviewers: austin, Phyx, hvr
    
    Reviewed By: Phyx
    
    Subscribers: thomie, rwbarton, erikd
    
    Differential Revision: https://phabricator.haskell.org/D3304


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b09bf4b0c0b01c1c53e972e52ceaeb28de66ae07
 configure.ac | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/configure.ac b/configure.ac
index 949c3d0..9864f32 100644
--- a/configure.ac
+++ b/configure.ac
@@ -446,7 +446,13 @@ fi
 # all be taken care of for us if we configured the subprojects using
 # AC_CONFIG_DIR, but unfortunately Cabal needs to be the one to do the
 # configuration.
-TargetPlatformFull="${target_alias}"
+if test -z "${target_alias}"
+then
+  # --target wasn't given; use result from AC_CANONICAL_TARGET
+  TargetPlatformFull="${target}"
+else
+  TargetPlatformFull="${target_alias}"
+fi
 AC_SUBST(CrossCompiling)
 AC_SUBST(CrossCompilePrefix)
 AC_SUBST(TargetPlatformFull)