build: avoid unnecessary execs of c++
commit3e51c5846c89a984b1f34800e1c68ee5b0a80d38
authorSaleem Abdulrasool <compnerd@compnerd.org>
Thu, 2 Feb 2017 19:05:28 +0000 (2 11:05 -0800)
committerHhvm Bot <hhvm-bot@users.noreply.github.com>
Thu, 2 Feb 2017 19:17:50 +0000 (2 11:17 -0800)
tree99530097a7e39ee70e216948f0d0138c0c472b36
parent73b96ad8228437aa2bf21480498b0acedbf9f0c7
build: avoid unnecessary execs of c++

Summary:
Use the cmake variable CMAKE_CXX_COMPILER_VERSION rather than manually
invoking the compiler to get the compiler version.
Closes https://github.com/facebook/hhvm/pull/7634

Differential Revision: D4481886

Pulled By: aorenste

fbshipit-source-id: e82f4575fbebe2e482b9c699ef530c7734b69481
CMake/HPHPCompiler.cmake