[GHC] #16083: objcpp-hi test appears to be broken on Mojave builder

[GHC]

#16083: objcpp-hi test appears to be broken on Mojave builder
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           Reporter:  bgamari         |             Owner:  (none)
               Type:  bug             |            Status:  new
           Priority:  normal          |         Milestone:
          Component:  Compiler        |           Version:  8.6.3
           Keywords:                  |  Operating System:  MacOS X
       Architecture:  x86_64 (amd64)  |   Type of failure:  None/Unknown
          Test Case:                  |        Blocked By:
           Blocking:                  |   Related Tickets:
Differential Rev(s):                  |         Wiki Page:
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 It appears that something has changed in the Darwin toolchain such that
 `<iostream>` is no longer found by default:
 {{{
 cd "driver/recomp001/recomp001.run" && $MAKE -s --no-print-directory
 recomp001
 Compile failed (exit code 1) errors were:
 warning: include path for stdlibc++ headers not found; pass '-std=libc++'
 on the command line to use the libc++ standard library instead
 [-Wstdlibcxx-not-found]

 objcpp-hi.mm:2:9: error:  fatal error: 'iostream' file not found
 #import <iostream>
         ^~~~~~~~~~
 1 warning and 1 error generated.
 `gcc' failed in phase `C Compiler'. (Exit code: 1)

 *** unexpected failure for objcpp-hi(normal)
 }}}

 Marking as broken.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16083>
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