[MacPorts] #56941: cmake @3.12.0_0 and gcc7 @7.3.0_3 don't work well together

[MacPorts]

#56941: cmake @3.12.0_0 and gcc7 @7.3.0_3 don't work well together
-------------------------+-----------------------
  Reporter:  iqgrande    |      Owner:  michaelld
      Type:  defect      |     Status:  assigned
  Priority:  Normal      |  Milestone:
 Component:  ports       |    Version:  2.5.3
Resolution:              |   Keywords:
      Port:  cmake, gcc  |
-------------------------+-----------------------

Comment (by mouse07410):

 Strange - your test case appears to work for me. MacOS 10.13.6,
 Xcode-9.4.1, current Macports, CMake, gcc8:
 {{{
 $ port select --list llvm
 Available versions for llvm:
         mp-llvm-5.0
         mp-llvm-6.0 (active)
         none
 $ port select --list gcc
 Available versions for gcc:
         mp-gcc7
         mp-gcc8 (active)
         none
 $ cmake .. -DCMAKE_C_COMPILER=/opt/local/bin/gcc-mp-8
 -- The C compiler identification is GNU 8.2.0
 -- The CXX compiler identification is AppleClang 9.1.0.9020039
 -- Checking whether C compiler has -isysroot
 -- Checking whether C compiler has -isysroot - yes
 -- Checking whether C compiler supports OSX deployment target flag
 -- Checking whether C compiler supports OSX deployment target flag - yes
 -- Check for working C compiler: /opt/local/bin/gcc-mp-8
 -- Check for working C compiler: /opt/local/bin/gcc-mp-8 -- works
 -- Detecting C compiler ABI info
 -- Detecting C compiler ABI info - done
 -- Detecting C compile features
 -- Detecting C compile features - done
 -- Check for working CXX compiler: /opt/local/bin/clang++
 -- Check for working CXX compiler: /opt/local/bin/clang++ -- works
 -- Detecting CXX compiler ABI info
 -- Detecting CXX compiler ABI info - done
 -- Detecting CXX compile features
 -- Detecting CXX compile features - done
 -- Configuring done
 -- Generating done
 -- Build files have been written to: /Users/ur20980/src/cmake-
 tst/tst3/build
 $ make
 Scanning dependencies of target test
 [ 50%] Building C object CMakeFiles/test.dir/main.c.o
 [100%] Linking C executable test
 [100%] Built target test
 $ ./test
 Hello world.
 $ rm -rf *
 $ cmake .. -DCMAKE_C_COMPILER=/opt/local/bin/gcc-mp-8
 -DCMAKE_CXX_COMPILER=/opt/local/bin/g++
 -- The C compiler identification is GNU 8.2.0
 -- The CXX compiler identification is GNU 8.2.0
 -- Checking whether C compiler has -isysroot
 -- Checking whether C compiler has -isysroot - yes
 -- Checking whether C compiler supports OSX deployment target flag
 -- Checking whether C compiler supports OSX deployment target flag - yes
 -- Check for working C compiler: /opt/local/bin/gcc-mp-8
 -- Check for working C compiler: /opt/local/bin/gcc-mp-8 -- works
 -- Detecting C compiler ABI info
 -- Detecting C compiler ABI info - done
 -- Detecting C compile features
 -- Detecting C compile features - done
 -- Checking whether CXX compiler has -isysroot
 -- Checking whether CXX compiler has -isysroot - yes
 -- Checking whether CXX compiler supports OSX deployment target flag
 -- Checking whether CXX compiler supports OSX deployment target flag - yes
 -- Check for working CXX compiler: /opt/local/bin/g++
 -- Check for working CXX compiler: /opt/local/bin/g++ -- works
 -- Detecting CXX compiler ABI info
 -- Detecting CXX compiler ABI info - done
 -- Detecting CXX compile features
 -- Detecting CXX compile features - done
 -- Configuring done
 -- Generating done
 -- Build files have been written to: /Users/ur20980/src/cmake-
 tst/tst3/build
 $ make
 Scanning dependencies of target test
 [ 50%] Building C object CMakeFiles/test.dir/main.c.o
 [100%] Linking C executable test
 [100%] Built target test
 $ ./test
 Hello world.
 $ echo $AS_INTEGRATED_ASSEMBLER
 1
 $
 }}}

-- 
Ticket URL: <https://trac.macports.org/ticket/56941#comment:7>
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