iOS patch no 3: enable/disable terminfo more precisely by os

[StephenBlackheath]

When cross compiling to iOS, HostOS = darwin and TargetOS = ios. darwin has termios but ios doesn't. So we need termios built in stage 0 but not stage 1, but the makefiles don't currently allow for that.

This patch makes it so termios is selected by the right OS for the right stage. I've refactored how Windows is handled here, so e.g. the termios selection should work correctly for both native windows and a Linux -> mingw32 cross compile (though I haven't tested it). Linux -> Windows mirrors darwin -> ios, in that it's termios -> no termios.

[StephenBlackheath]

iOS patch 3 rev a: disable terminfo by OS

[StephenBlackheath]

Thanks for the previous commits and apologies for forgetting a ;;

I hope this makes sense. The reason why I can't just leave out $(eval $(call addPackage,terminfo)) like the existing code does with Windows is that if we do that, then the terminfo never gets included at all. That's because it doesn't get added to PACKAGES_STAGE1 so the code below never includes the module. That's no good to us because we need it built in stage 0.

ifneq "$(CLEANING)" "YES"
BUILD_DIRS += \
   $(patsubst %, libraries/%, $(PACKAGES_STAGE1))
endif

[StephenBlackheath]

iOS patch 3 rev b: disable terminfo by os - fixes a makefile loop introduced in 3a (affecting ios only)

[StephenBlackheath]

iOS patch 3 rev c: disable terminfo by os - oops - slight mistake

[StephenBlackheath]

iOS patch 3 rev d: disable terminfo by os - OK now I have the bugs out.

[StephenBlackheath]

iOS patch 3 rev e: disable terminfo by os - finally I think I have it right this time

[StephenBlackheath]

That was tricky. With 3e I tested a native linux build and an ios cross build to the start of the stage2 compiler, so I'm very confident now. So, please review.

[simonmar]

Things have got complicated in this bit of the build system with lots of exceptions, I think it needs a good refactoring. We should specify the stages for each package separately, perhaps.

[ian@…]

commit dd9da49ceda5bd0d6c860604ace0ca9829199fe5

Author: Ian Lynagh <ian@well-typed.com>
Date:   Fri Mar 1 22:29:19 2013 +0000

    Fix when terminfo is built; fixes #7700
    
    We now use the 'host' to determine whether stage0 builds terminfo,
    and 'target' to determine whether stage1 does.
    
    We don't build it if the platform is either Windows or ios.

 ghc.mk           |    6 +++++-
 mk/project.mk.in |    7 +++++++
 2 files changed, 12 insertions(+), 1 deletions(-)

[igloo]

Thanks for the patch. I've refactored that area of the build system, as Simon suggested, and I think it has the behaviour you want now. Please let me know if not.

[StephenBlackheath]

Your changes don't quite fix it for darwin -> iOS, because of this sequence of events:

1. On a darwin -> iOS, PACKAGES_STAGE0 gets terminfo but PACKAGES_STAGE1 doesn't.

2. This line works for everything in PACKAGES_STAGE1, but there's no similar line for PACKAGES_STAGE0 BUILD_DIRS += $(patsubst %, libraries/%, $(PACKAGES_STAGE1))

3. So libraries/terminfo never gets added to BUILD_DIRS.

The output is this:

Configuring ghc-pkg-6.9...
ghc-cabal: At least the following dependencies are missing:
terminfo ==0.3.2.5
make[1]: *** [utils/ghc-pkg/dist/package-data.mk] Error 1
make: *** [all] Error 2

I attach a patch to fix it. When working on it before I suspected some order dependence in the inclusion of the build dirs, and I haven't sanity tested a complete build yet.

[StephenBlackheath]

Add PACKAGES_STAGE0 entries to BUILD_DIRS

[StephenBlackheath]

I completed a darwin -> iOS cross build successfully with this patch, so there's a good chance the potential slight change in ordering of BUILD_DIRS is OK.

[ian@…]

commit 056997a285a368f5f78905b4b325a3258484f71d

Author: Ian Lynagh <ian@well-typed.com>
Date:   Sun Mar 3 13:35:41 2013 +0000

    Add PACKAGES_STAGE0 to build-dirs too; fixes #7700
    
    This is sometimes needed when cross-compiling, as some packages may be
    built in stage 0 but not stage 1.
    
    In order to make everything work out, this also removes the requirement
    that the build-dirs are in dependency order

 ghc.mk           |   16 ++++++++--------
 rules/haddock.mk |    5 ++++-
 2 files changed, 12 insertions(+), 9 deletions(-)

[igloo]

There was a potential dependency problem with the haddock rules, but I've fixed that, and added the STAGE0 packages to BUILD_DIRS.