Hi, There is a bit of unexpected behaviour in the `shell` function (due to the undocumented fact that it sometimes avoids actually calling the shell):
``` $ cat Makefile FOO:=$(shell ./foo.sh) $ cat foo.sh #!/bin/ohno echo hi $ make make: ./foo.sh: No such file or directory make: *** No targets. Stop. $ ./foo.sh zsh: ./foo.sh: bad interpreter: /bin/ohno: no such file or directory ``` The “no such file or directory” error from Make is very confusing and unexpected in this situation, especially given that it is not the error that the shell would return. The reason for it is that, while undocumented, the `shell` function will try to avoid calling the shell in simple cases like this one and will directly exec the command. However, the error returned by `execve` is ambiguous: > ENOENT The file pathname or a script or ELF interpreter does not exist. Shells (bash, zsh) disambiguate it themselves, i.e. there is extra logic for the case of ENOENT, while Make simply fails with what it sees, resulting in a puzzling error message. Cheers, Kirill
