cmake for Gasnet broken

when using the lates version of sac2c (3cf8846b), make fails if gasnet is not available:

-- Using `/Volumes/Users/sbs/sac2c/build_d/cb' for code-beautification
-- Distmem/Shray only supports Linux
CMake Error at cmake/sac2c/distmem-related.cmake:13 (IF):
  if given arguments:

    "NOT" "(" "DEFINED" "ENV{GASNet_ROOT}" "OR" ")"

  Unknown arguments specified
Call Stack (most recent call first):
  cmake/sac2c/config.cmake:526 (CHECK_DISTMEM_GASNET)
  CMakeLists.txt:46 (INCLUDE)


-- Configuring incomplete, errors occurred!