Package keys (for linking/type equality) separated from package IDs.

This patch set makes us no longer assume that a package key is a human
readable string, leaving Cabal free to "do whatever it wants" to allocate
keys; we'll look up the PackageId in the database to display to the user.
This also means we have a new level of qualifier decisions to make at the
package level, and rewriting some Safe Haskell error reporting code to DTRT.

Additionally, we adjust the build system to use a new ghc-cabal output
Make variable PACKAGE_KEY to determine library names and other things,
rather than concatenating PACKAGE/VERSION as before.

Adds a new `-this-package-key` flag to subsume the old, erroneously named
`-package-name` flag, and `-package-key` to select packages by package key.

RFC: The md5 hashes are pretty tough on the eye, as far as the file
system is concerned :(

ToDo: safePkg01 test had its output updated, but the fix is not really right:
the rest of the dependencies are truncated due to the fact the we're only
grepping a single line, but ghc-pkg is wrapping its output.

ToDo: In a later commit, update all submodules to stop using -package-name
and use -this-package-key.  For now, we don't do it to avoid submodule
explosion.

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Test Plan: validate

Reviewers: simonpj, simonmar, hvr, austin

Subscribers: simonmar, relrod, carter

Differential Revision: https://phabricator.haskell.org/D80

1 files changed, 16 insertions, 4 deletions

diff --git a/rules/distdir-way-opts.mk b/rules/distdir-way-opts.mk
index 93bc60b6b1..898485c0ca 100644
--- a/rules/distdir-way-opts.mk
+++ b/rules/distdir-way-opts.mk
@@ -81,6 +81,18 @@ 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.
 
+# ToDo: It would be more accurate to version test this against what version of
+# GHC we're using to see if it understands package-key
+ifeq "$4" "0"
+$1_$2_$4_DEP_OPTS = \
+ $$(foreach pkg,$$($1_$2_DEPS),-package $$(pkg))
+$4_THIS_PACKAGE_KEY = -package-name
+else
+$1_$2_$4_DEP_OPTS = \
+ $$(foreach pkg,$$($1_$2_DEP_KEYS),-package-key $$(pkg))
+$4_THIS_PACKAGE_KEY = -this-package-key
+endif
+
 $1_$2_$3_MOST_HC_OPTS = \
  $$(WAY_$3_HC_OPTS) \
  $$(CONF_HC_OPTS) \
@@ -88,7 +100,7 @@ $1_$2_$3_MOST_HC_OPTS = \
  $$($1_HC_OPTS) \
  $$($1_$2_HC_PKGCONF) \
  $$(if $$($1_$2_PROG),, \
-        $$(if $$($1_PACKAGE),-package-name $$($1_PACKAGE)-$$($1_$2_VERSION))) \
+        $$(if $$($1_PACKAGE),$$($4_THIS_PACKAGE_KEY) $$($1_$2_PACKAGE_KEY))) \
  $$(if $$($1_PACKAGE),-hide-all-packages) \
  -i $$(if $$($1_$2_HS_SRC_DIRS),$$(foreach dir,$$($1_$2_HS_SRC_DIRS),-i$1/$$(dir)),-i$1) \
  -i$1/$2/build -i$1/$2/build/autogen \
@@ -98,7 +110,7 @@ $1_$2_$3_MOST_HC_OPTS = \
  $$(foreach inc,$$($1_$2_INCLUDE),-\#include "$$(inc)") \
  $$(foreach opt,$$($1_$2_CPP_OPTS),-optP$$(opt)) \
  $$(if $$($1_PACKAGE),-optP-include -optP$1/$2/build/autogen/cabal_macros.h) \
- $$(foreach pkg,$$($1_$2_DEPS),-package $$(pkg)) \
+ $$($1_$2_$4_DEP_OPTS) \
  $$($1_$2_HC_OPTS) \
  $$(CONF_HC_OPTS_STAGE$4) \
  $$($1_$2_MORE_HC_OPTS) \
@@ -170,11 +182,11 @@ ifneq "$4" "0"
 ifeq "$$(TargetElf)" "YES"
 $1_$2_$3_GHC_LD_OPTS += \
     -fno-use-rpaths \
-    $$(foreach d,$$($1_$2_TRANSITIVE_DEPS),-optl-Wl$$(comma)-rpath -optl-Wl$$(comma)'$$$$ORIGIN/../$$d') -optl-Wl,-zorigin
+    $$(foreach d,$$($1_$2_TRANSITIVE_DEP_KEYS),-optl-Wl$$(comma)-rpath -optl-Wl$$(comma)'$$$$ORIGIN/../$$d') -optl-Wl,-zorigin
 else ifeq "$$(TargetOS_CPP)" "darwin"
 $1_$2_$3_GHC_LD_OPTS += \
     -fno-use-rpaths \
-    $$(foreach d,$$($1_$2_TRANSITIVE_DEPS),-optl-Wl$$(comma)-rpath -optl-Wl$$(comma)'@loader_path/../$$d')
+    $$(foreach d,$$($1_$2_TRANSITIVE_DEP_KEYS),-optl-Wl$$(comma)-rpath -optl-Wl$$(comma)'@loader_path/../$$d')
 endif
 endif
 endif