From: Jesper Dangaard Brouer
> Sent: 26 April 2016 17:27
> Make compiling samples/bpf more user friendly, by detecting if LLVM
> compiler tool 'llc' is available, and also detect if the 'bpf' target
> is available in this version of LLVM.
...
> diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
> index 5bae9536f100..45859c99f573 100644
> --- a/samples/bpf/Makefile
> +++ b/samples/bpf/Makefile
> @@ -85,6 +85,24 @@ HOSTLOADLIBES_test_overhead += -lelf -lrt
> # make samples/bpf/ LLC=~/git/llvm/build/bin/llc
> LLC ?= llc
>
> +# Verify LLVM compiler is available and bpf target is supported
> +.PHONY: verify_cmd_llc verify_target_bpf
> +
> +verify_cmd_llc:
> + @if ! (which "${LLC}" > /dev/null 2>&1); then \
You should use 'type' not 'which'.
'type' is a posix shell builtin, 'which' is a script/program
that tries to emulate a 'csh' builtin.
You want to know whether the shell that make runs can execute ${LLC}
not whether a csh would be able to run it.
You might also want to worry about:
LLC="/path_to_llc/llc -extra_arg" make fubar
David
