On Tue, Jul 21, 2015 at 4:21 PM, Simon Peyton Jones <simonpj@microsoft.com> wrote:

Friends

With the new build system I get this kind of output

  HC [stage 1] compiler/stage2/build/SPARC/AddrMode.o

  HC [stage 1] compiler/stage2/build/CmmContFlowOpt.o

  HC [stage 1] compiler/stage2/build/CmmImplementSwitchPlans.o

  AR libraries/Cabal/Cabal/dist-install/build/libHSCabal-1.23.0.0-752LrSyTT7YLYxOzpNXfM5.a

C:\fp\HP-2014-2.0.0.0\mingw\bin\ar.exe: creating libraries/Cabal/Cabal/dist-install/build/libHSCabal-1.23.0.0-752LrSyTT7YLYxOzpNXfM5.a

  LD libraries/Cabal/Cabal/dist-install/build/HSCabal-1.23.0.0-752LrSyTT7YLYxOzpNXfM5.o

  HC [stage 1] utils/ghc-cabal/dist-install/build/Main.o

WARNING: file compiler\specialise\Specialise.hs, line 724

I assume this is when you run validate?

But I have no idea which module caused the WARNING, nor do I have a command-line to copy/paste to reproduce it.  (With the old module-at-a-time system I could copy/paste the command line for the specific module.)

Is there a way to

·        make things sequential so I can tell which warnings from which module

make -j1, which is make's default, but validate invokes make with -j2 or higher (depending on how many CPUs it thinks your system has).

·        get a command line to copy/paste to compile that module?

validate sets the GHC build system variable V=0 in mk/are-validating.mk. You can override it from the make command line with make V=1.

So, you can run "make V=1" to restart the build serially and with the command to build each file displayed. Note that serial make may build modules in a different order than parallel make, so it may take a while for make to get around to building the module that failed.

Regards,
Reid Barton