[commit: ghc] ghc-8.0: Fix bootstrapping with GHC 7.8. (36e1fea)

[git at git.haskell.org]

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

On branch  : ghc-8.0
Link       : http://ghc.haskell.org/trac/ghc/changeset/36e1fead2fa63ad3d73d2e0fafbb305ff35cd08a/ghc

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

commit 36e1fead2fa63ad3d73d2e0fafbb305ff35cd08a
Author: Edward Z. Yang <ezyang at cs.stanford.edu>
Date:   Wed Jan 20 11:22:43 2016 +0100

    Fix bootstrapping with GHC 7.8.
    
    Test Plan: bootstrap with GHC 7.8
    
    Reviewers: hvr, austin, bgamari
    
    Reviewed By: bgamari
    
    Subscribers: thomie
    
    Differential Revision: https://phabricator.haskell.org/D1803


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

36e1fead2fa63ad3d73d2e0fafbb305ff35cd08a
 mk/config.mk.in           |  1 +
 rules/distdir-way-opts.mk | 18 +++++++++++-------
 2 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/mk/config.mk.in b/mk/config.mk.in
index fcc4b8a..a8581e3 100644
--- a/mk/config.mk.in
+++ b/mk/config.mk.in
@@ -500,6 +500,7 @@ GHC_PACKAGE_DB_FLAG = @GHC_PACKAGE_DB_FLAG@
 
 CMM_SINK_BOOTSTRAP_IS_NEEDED = @CMM_SINK_BOOTSTRAP_IS_NEEDED@
 
+SUPPORTS_COMPONENT_ID = @SUPPORTS_COMPONENT_ID@
 SUPPORTS_THIS_UNIT_ID = @SUPPORTS_THIS_UNIT_ID@
 
 #-----------------------------------------------------------------------------
diff --git a/rules/distdir-way-opts.mk b/rules/distdir-way-opts.mk
index 66c00af..f099d4e 100644
--- a/rules/distdir-way-opts.mk
+++ b/rules/distdir-way-opts.mk
@@ -96,18 +96,22 @@ define distdir-way-opts # args: $1 = dir, $2 = distdir, $3 = way, $4 = stage
 # $1_$2_$3_MOST_HC_OPTS is also passed to C compilations when we use
 # GHC as the C compiler.
 
-ifeq "$(SUPPORTS_THIS_UNIT_ID)" "NO"
-ifeq "$4" "0"
-$4_USE_THIS_UNIT_ID=NO
-endif
-endif
-
 $1_$2_$4_DEP_OPTS = \
  $$(foreach pkg,$$($1_$2_DEP_IPIDS),-package-id $$(pkg))
 
-ifeq "$($4_USE_THIS_UNIT_ID)" "NO"
+# These are really all misnomers; SUPPORTS_COMPONENT_ID just tests for >=7.9
+# and SUPPORTS_THIS_UNIT_ID >=7.11
+ifeq "$4" "0"
+ifeq "$(SUPPORTS_THIS_UNIT_ID)" "YES"
+$4_THIS_UNIT_ID = -this-unit-id
+else
+ifeq "$(SUPPORTS_COMPONENT_ID)" "YES"
 $4_THIS_UNIT_ID = -this-package-key
 else
+$4_THIS_UNIT_ID = -package-name
+endif
+endif
+else
 $4_THIS_UNIT_ID = -this-unit-id
 endif