GOOS=ios GOARCH=amd64 CGO_ENABLED=1 CC=$(go env GOROOT)/misc/ios/clangwrap.sh go build

Setting CC is not necessary if the toolchain is built with CC_FOR_TARGET set.

To use the go tool to run individual programs and tests, put $GOROOT/bin into PATH to ensure
the go_ios_$GOARCH_exec wrapper is found. For example, to run the archive/tar tests:

	export PATH=$GOROOT/bin:$PATH

but may nonetheless break some existing programs,
we first engineer the change to keep as many existing programs working as possible.
For the remaining programs,
we define a new GODEBUG setting that
allows individual programs to opt back in to the old behavior.
A GODEBUG setting may not be added if doing so is infeasible,
but that should be extremely rare.

GODEBUG settings added for compatibility will be maintained