diff options
author | Quentin Monnet <quentin@isovalent.com> | 2021-10-06 12:10:49 +0100 |
---|---|---|
committer | Andrii Nakryiko <andrii@kernel.org> | 2021-10-06 12:34:02 -0700 |
commit | 929bef467771d4d5a22b9edb51a2025dc0e49113 (patch) | |
tree | e33de0738babed1771644a310480924107c8efdc /tools/lib/bpf/Makefile | |
parent | 90982e13561e0d8df91d49658d3bf068ae9f2dff (diff) |
bpf: Use $(pound) instead of \# in Makefiles
Recent-ish versions of make do no longer consider number signs ("#") as
comment symbols when they are inserted inside of a macro reference or in
a function invocation. In such cases, the symbols should not be escaped.
There are a few occurrences of "\#" in libbpf's and samples' Makefiles.
In the former, the backslash is harmless, because grep associates no
particular meaning to the escaped symbol and reads it as a regular "#".
In samples' Makefile, recent versions of make will pass the backslash
down to the compiler, making the probe fail all the time and resulting
in the display of a warning about "make headers_install" being required,
even after headers have been installed.
A similar issue has been addressed at some other locations by commit
9564a8cf422d ("Kbuild: fix # escaping in .cmd files for future Make").
Let's address it for libbpf's and samples' Makefiles in the same
fashion, by using a "$(pound)" variable (pulled from
tools/scripts/Makefile.include for libbpf, or re-defined for the
samples).
Reference for the change in make:
https://git.savannah.gnu.org/cgit/make.git/commit/?id=c6966b323811c37acedff05b57
Fixes: 2f3830412786 ("libbpf: Make libbpf_version.h non-auto-generated")
Fixes: 07c3bbdb1a9b ("samples: bpf: print a warning about headers_install")
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211006111049.20708-1-quentin@isovalent.com
Diffstat (limited to 'tools/lib/bpf/Makefile')
-rw-r--r-- | tools/lib/bpf/Makefile | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile index 0f766345506f..41e4f78dbad5 100644 --- a/tools/lib/bpf/Makefile +++ b/tools/lib/bpf/Makefile @@ -208,8 +208,8 @@ check_abi: $(OUTPUT)libbpf.so $(VERSION_SCRIPT) exit 1; \ fi -HDR_MAJ_VERSION := $(shell grep -oE '^\#define LIBBPF_MAJOR_VERSION ([0-9]+)$$' libbpf_version.h | cut -d' ' -f3) -HDR_MIN_VERSION := $(shell grep -oE '^\#define LIBBPF_MINOR_VERSION ([0-9]+)$$' libbpf_version.h | cut -d' ' -f3) +HDR_MAJ_VERSION := $(shell grep -oE '^$(pound)define LIBBPF_MAJOR_VERSION ([0-9]+)$$' libbpf_version.h | cut -d' ' -f3) +HDR_MIN_VERSION := $(shell grep -oE '^$(pound)define LIBBPF_MINOR_VERSION ([0-9]+)$$' libbpf_version.h | cut -d' ' -f3) check_version: $(VERSION_SCRIPT) libbpf_version.h @if [ "$(HDR_MAJ_VERSION)" != "$(LIBBPF_MAJOR_VERSION)" ]; then \ |