[commit: ghc] master: Introduce a $tooldir variable for nicer toolchain detection on Windows (5d76846)

[git at git.haskell.org]

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

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/5d76846405240c051b00cddcda9d8d02c880968e/ghc

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commit 5d76846405240c051b00cddcda9d8d02c880968e
Author: Alp Mestanogullari <alp at well-typed.com>
Date:   Tue Apr 17 23:04:11 2018 +0100

    Introduce a $tooldir variable for nicer toolchain detection on Windows
    
    Summary:
    This patch affects several files that affect how we detect mingw and perl
    on Windows. The initial motivation is:
    
        https://github.com/snowleopard/hadrian/issues/564
    
    where, with Hadrian building relocatable (non-inplace) GHCs, the current
    detection mechanism falls short by e.g only trying $topdir/../mingw. But
    in Hadrian, for reasons given in that issue, we would need to store e.g mingw
    under $topdir/../../mingw except for binary distributions, where we want
    to follow the existing structure, in which case $topdir/../mingw is correct. So
    we need to support both, which is what this patch hopefully implements.
    
    Test Plan: ./validate
    
    Reviewers: Phyx, hvr, bgamari, erikd
    
    Reviewed By: Phyx
    
    Subscribers: snowleopard, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4598


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5d76846405240c051b00cddcda9d8d02c880968e
 aclocal.m4                        | 16 +++++-----
 compiler/main/SysTools.hs         | 24 +++++++++------
 compiler/main/SysTools/BaseDir.hs | 64 +++++++++++++++++++++++++++++++++++----
 3 files changed, 80 insertions(+), 24 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 5d76846405240c051b00cddcda9d8d02c880968e