hydra: Clarify the dependency on BDW-GC.

Dependencies

• [2] X5QBLQDG
• [3] QK2OXCKP hydra/release.nix: move manual to tarball build, restore version in store path for tarball build
• [4] 2KJFOYGS hydra: Actually check for Nix in `configure'.
• [5] VM3TQZ65 * hydra: make manual.pdf
• [6] YQWH4POV * Simplify.
• [7] T4LLYESZ * Nix expression for building Hydra.
• [8] U2BNO3C5 hydra: fix build job
• [9] FV2M6MOT hydra: use autoconf/-make
• [10] UHMUHQMU hydra: fix tarball build, add pre suffix to tarballs
• [*] 4N5APGRG * Start of a helper tool to evaluate job expressions efficiently.

Change contents

• edit in configure.ac at line 44
  [4.462]

  [5.16382]
  +

  + PKG_CHECK_MODULES([BDW_GC], [bdw-gc])
• replacement in release.nix at line 18
  [5.75]→[3.46:114](∅→∅)
  − buildInputs = [ perl libxslt dblatex tetex nukeReferences ] ;
  [5.75]

  [5.76]
  + buildInputs =

  + [ perl libxslt dblatex tetex nukeReferences pkgconfig boehmgc ] ;
• replacement in release.nix at line 50
  [5.1780]→[2.0:70](∅→∅)
  − [ perl makeWrapper libtool nix unzip nukeReferences boehmgc ]
  [5.1780]

  [5.1817]
  + [ perl makeWrapper libtool nix unzip nukeReferences pkgconfig boehmgc ]
• replacement in src/c/Makefile.am at line 4
  [5.18008]→[5.18008:18101](∅→∅)
  − hydra_eval_jobs_LDADD = -lmain -lexpr -L$(nix)/lib/nix

  − AM_CXXFLAGS = \

  − -I$(nix)/include/nix
  [5.18008]
  + hydra_eval_jobs_LDADD = -lmain -lexpr -L$(nix)/lib/nix $(BDW_GC_LIBS)

  +

  + AM_CXXFLAGS = \

  + -I$(nix)/include/nix \

  + $(BDW_GC_CFLAGS)
• edit in src/c/hydra_eval_jobs.cc at line 3
  [12.339]

  [12.339]
  +

  + #include <gc/gc_allocator.h>