SPI only: make COMPILER=clang or =gcc use the default clang or gcc in execution path.
SPI only: make COMPILER=clang or =gcc use the default clang or gcc in execution path.

bdeluca/oiio,lgritz/oiio,micler/oiio,OpenImageIO/oiio,sambler/oiio,cwilling/oiio,YangYangTL/oiio,YangYangTL/oiio,lgritz/oiio,micler/oiio,scott-wilson/oiio,cwilling/oiio,mcanthony/oiio,micler/oiio,lgritz/oiio,mcanthony/oiio,scott-wilson/oiio,mcanthony/oiio,sambler/oiio,lgritz/oiio,scott-wilson/oiio,OpenImageIO/oiio,YangYangTL/oiio,YangYangTL/oiio,bdeluca/oiio,scott-wilson/oiio,bdeluca/oiio,micler/oiio,sambler/oiio,OpenImageIO/oiio,sambler/oiio,mcanthony/oiio,cwilling/oiio,bdeluca/oiio,OpenImageIO/oiio,cwilling/oiio