ghc @7.8.3: segmentation fault during build

[kkbt]

Build of ghc fails when trying to install port pandoc.
A segmentation fault is reported:

	:info:build make[1]: *** [compiler/stage2/dll-split.stamp] Segmentation fault: 11

The OS and software versions are:

MacBook Air with Mac OS X 10.11.6 (15G1217)
with current MacPorts 2.4.1

ports:
pandoc @1.12.4.2_1 (textproc)
ghc @7.8.3_5 (lang, haskell)

The command was:

	sudo port -N install pandoc

Surprisingly, an installation a day earlier on a MacBook with identical OS and software versions was successful.

Logs are attached.

[kkbt]

Logs

[mf2k (Frank Schima)]

The Priority field is for Macports Developers only. Please do not set it.

[ryandesign (Ryan Carsten Schmidt)]

Please attach the entire main.log (compressed if large).

[mojca (Mojca Miklavec)]

Here are the logs (not necessarily failing for the same reason):

• ​10.11
• ​10.8
• ​10.6_i386 - see also #51766, #50962
• ​10.5_ppc - fails because of dependency on clang-3.5 which doesn't support ppc

It is worth noting that ghc builds just fine on 10.6/x86_64, 10.7, 10.9, 10.10, 10.12.

Now, if you take a look at the blacklist:

# Compilation fails with older versions of clang. clang-4.1 from Xcode 4.5 is
# too old, clang-5.1 from from Xcode 5.1 works. I do not have any data points in
# between, so I'm blacklisting everything lower than 5.1. If you want to test
# the versions in between, be my guest.
# Also avoid LLVM GCC 4.2 and GCC 4.2, which are before MacPorts' clang 3.4 in
# the fallback list on some systems.
# NOTE that it is actually the C compiler used in ghc-bootstrap that is
# relevant here. This code block is duplicated in this port to avoid
# inconsistencies.
compiler.blacklist-append \
                llvm-gcc-4.2 \
                gcc-4.2 \
                {clang < 503.0.38} \
                macports-clang-3.3

the clang < 503.0.38 blacklists the system compiler on 10.7 and earlier, but not on 10.8 and later. It could be that the system compiler on 10.8 is simply no longer up to the task. I guess that blacklisting clang on 10.8 would solve the problem on that OS, but that's probably orthogonal to the problem on 10.11.

Do we have anyone with 10.8?

Does anyone have ideas about 10.11?

[kencu (Ken)]

I think ghc may not available for i386 any more - there is no ghc-bootstrap compiler available for i386. Likewise ppc is no longer available (although I see there is an older version for 10.5 ppc that can be installed from a binary if that ever really matters to anybody, and an even older version for 10.4 PPC).

The failure on 10.8 is almost certainly because the clang version written into /opt/local/share/ghc-bootstrap/libexec/clang-wrapper in the installed binary is missing when ghc-bootstrap is reinstalled from a binary.

I don't have any idea why the build segfaults on 10.11, tho.

[kencu (Ken)]

In b6060617db664a7ca586df1d8894da2054f7db75/macports-ports:

ghc and ghc-bootstrap: specify compiler to clang-4.0

on older systems and on 10.11
and add a build and runtime dependency for clang-4.0
as this compiler needs to be present when ghc is used.
closes: #54363
closes: #53709
closes: #50962
closes: #50480