Explicitly set PREFIX=/ when installing embedded libbpf headers #476
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Thanks for the patch! If we're setting this explicitly, I'm wondering whether we shouldn't just drop |
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I haven't tested it but I would imagine it would work fine. |
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Alright, please update the PR to do that, then :) |
When xdp-tools builds the embedded copy of libbpf, it invokes the libbpf
build system to installs it headers, and then constructs a path to
those embedded libbpf headers [0] based on the assumption that libbpf
installed its headers into its default PREFIX value of /usr.
However, if PREFIX is passed to the xdp-tools build system, this
variable gets passed down to the invocation of the libbpf build system
as well, and libbpf installs its headers into a different directory
that doesn't match xdp-tools' LIBBPF_INCLUDE_DIR variable, and the build
fails like this:
$ make PREFIX=/usr/local
[…]
libbpf support: Submodule 'libbpf' (https://github.com/libbpf/libbpf.git) registered for path 'lib/libbpf'
Cloning into '/home/edmonds/src/xdp-tools/lib/libbpf'...
Submodule path 'lib/libbpf': checked out 'fdf402b384cc42ce29bb9e27011633be3cbafe1e'
submodule v1.4.0
[…]
lib
libbpf
CC libbpf/src/libbpf.a
INSTALL libbpf/src/libbpf.a
libxdp
CC staticobjs/libxdp.o
libxdp.c:31:10: fatal error: bpf/libbpf.h: No such file or directory
31 | #include <bpf/libbpf.h>
| ^~~~~~~~~~~~~~
compilation terminated.
This commit explicitly passes PREFIX=/ to the libbpf build system
when installing the embedded libbpf headers, and also updates the
LIBBPF_INCLUDE_DIR variable in the xdp-tools build system to match the
resulting include path, so that the embedded libbpf headers are
installed into a fixed location.
[0]: https://github.com/xdp-project/xdp-tools/blob/7b3bbe2f6f16d658bb09a7b7e5958f4a49825ee6/configure#L382
Signed-off-by: Robert Edmonds <[email protected]>
edmonds
changed the title
Done. |
tohojo
approved these changes
Feb 26, 2025
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When xdp-tools builds the embedded copy of libbpf, it invokes the libbpf build system to installs it headers, and then constructs a path to those embedded libbpf headers based on the assumption that libbpf installed its headers into its default PREFIX (which appears to be /usr):
xdp-tools/configure
Line 382 in 7b3bbe2
However, if PREFIX is passed to the xdp-tools build system, this variable gets passed down to the invocation of the libbpf build system as well, and libbpf installs its headers into a different directory that doesn't match xdp-tools' LIBBPF_INCLUDE_DIR variable, and the build fails like this:
This commit explicitly passes PREFIX=/usr to the libbpf build system when installing the embedded libbpf headers so that xdp-tools' LIBBPF_INCLUDE_DIR variable still matches the path to those headers.