ghc @9.4.2_1: destroot does not use the right compiler

[larryv (Lawrence Velázquez)]

The destroot phase runs a configure script (???) but allows it to use the default gcc instead of forcing it to use the right compiler. This fails for me because my MacPorts installation is set up to catch it, but I expect it "succeeds" for most users.

• main.log excerpt:

  :info:destroot Command line: sh configure --prefix=/opt/local/var/macports/build/_Users_larryv_Code_MacPorts_ports_lang_ghc/ghc/work/destroot/opt/local
  :info:destroot ===> Command failed with error code: 77
  :info:destroot configure: error: in `/opt/local/var/macports/build/_Users_larryv_Code_MacPorts_ports_lang_ghc/ghc/work/ghc-9.4.2/_build/bindist/ghc-9.4.2-x86_64-apple-darwin':
  :info:destroot configure: error: C compiler cannot create executables
  :info:destroot See `config.log' for more details
  

• work/ghc-9.4.2/_build/bindist/ghc-9.4.2-x86_64-apple-darwin/config.log excerpt:

  configure:4465: checking for gcc
  configure:4486: found /opt/local/libexec/no_default_gcc/gcc
  configure:4497: result: gcc
  configure:4528: checking for C compiler version
  configure:4537: gcc --version >&5
  gcc --version
  gcc: Error: You should be using ${configure.cc}
  See https://trac.macports.org/wiki/UsingTheRightCompiler
  configure:4548: $? = 1
  

The following change does force the right compiler to be found, but the ghc port is so complex that I don't know whether it is correct, let alone the best possible fix.

lang/ghc/Portfile

@@ -103 +103 @@
     build.pre_args
     build.post_args [haskell_cabal.build_getjobsarg]
 
+    destroot.env    CC=${configure.cc} \
+                    CXX=${configure.cxx}
     destroot.cmd    hadrian
     destroot.target install
     destroot.pre_args \

[larryv (Lawrence Velázquez)]

work/ghc-9.4.2/_build/bindist/ghc-9.4.2-x86_64-apple-darwin/config.log

[essandess (Steve Smith)]

Do you observe this issue only in destroot and not in build as well?

[Steve Smith <essandess@…>]

In ce58ed87dd5e3902321103209d2a557490090c57/macports-ports (master):

ghc: use correct compiler

• Fixes: #65899

[larryv (Lawrence Velázquez)]

Replying to essandess:

Do you observe this issue only in destroot and not in build as well?

That's right; the build phase does not appear to call default compilers via PATH search.

[essandess (Steve Smith)]

In c4955daea49bcd389b2daee486bf1e678bc4dd8d/macports-ports (master):

ghc: use correct compiler

• Fixes: ​https://github.com/macports/macports-ports/pull/16223#issuecomment-1257223539
• Fixes: #65899

[larryv (Lawrence Velázquez)]

Replying to essandess:

In c4955daea49bcd389b2daee486bf1e678bc4dd8d/macports-ports (master):

ghc: use correct compiler

• Fixes: ​https://github.com/macports/macports-ports/pull/16223#issuecomment-1257223539
• Fixes: #65899

Just confirming that the previous commit didn't fix the issue, but this one did. Thank you!