tree 93f5b7898e3909926662071f591309354ad730b2
parent 7e3cbd3405cb7b6c036b8984baa694bc55c08e46
author Quentin Monnet <quentin@isovalent.com> 1633635867 +0100
committer Andrii Nakryiko <andrii@kernel.org> 1633718854 -0700

libbpf: Skip re-installing headers file if source is older than target

The "install_headers" target in libbpf's Makefile would unconditionally
export all API headers to the target directory. When those headers are
installed to compile another application, this means that make always
finds newer dependencies for the source files relying on those headers,
and deduces that the targets should be rebuilt.

Avoid that by making "install_headers" depend on the source header
files, and (re-)install them only when necessary.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211007194438.34443-2-quentin@isovalent.com