ISPC

在 3.19 版被加入.

這是一個 CMake 環境變數。其初始值取自呼叫的進程環境。

Preferred executable for compiling ISPC language files. Will only be used by CMake on the first configuration to determine ISPC compiler, after which the value for ISPC is stored in the cache as CMAKE_ISPC_COMPILER. For any configuration run (including the first), the environment variable will be ignored if the CMAKE_ISPC_COMPILER variable is defined.