gyp: Inherit CC/CXX for CC/CXX.host
Checklist
-
tests and code linting passes -
the commit message follows commit guidelines
Affected core subsystem(s)
tools/gyp
Description of change
Gyp defaults to gcc/g++ if CC.host/CXX.host is unset. This is not suitable for environments that only uses the clang toolchain.
Since we already assume that the user will provide clang/clang++ through CC/CXX, lean against it (then drop to gcc/g++).
I don't think this will be accepted upstream but I guess I should give it a try.
Refs #6088 and fixes #6152 (closed). /cc @srl295, @bnoordhuis.