mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2025-01-23 16:53:58 -05:00
5a6ea7022f
Commit [0] breaks samples/bpf build:
$ make M=samples/bpf
...
make -C /path/to/kernel/samples/bpf/../../tools/lib/bpf \
...
EXTRA_CFLAGS=" \
...
-fsanitize=bounds \
-I/path/to/kernel/usr/include \
...
/path/to/kernel/samples/bpf/libbpf/libbpf.a install_headers
CC /path/to/kernel/samples/bpf/libbpf/staticobjs/libbpf.o
In file included from libbpf.c:29:
/path/to/kernel/tools/include/linux/err.h:35:8: error: 'inline' can only appear on functions
35 | static inline void * __must_check ERR_PTR(long error_)
| ^
The error is caused by `objtree` variable changing definition from `.`
(dot) to an absolute path:
- The variable TPROGS_CFLAGS is constructed as follows:
...
TPROGS_CFLAGS += -I$(objtree)/usr/include
- It is passed as EXTRA_CFLAGS for libbpf compilation:
$(LIBBPF): ...
...
$(MAKE) -C $(LIBBPF_SRC) RM='rm -rf' EXTRA_CFLAGS="$(TPROGS_CFLAGS)"
- Before commit [0], the line passed to libbpf makefile was
'-I./usr/include', where '.' referred to LIBBPF_SRC due to -C flag.
The directory $(LIBBPF_SRC)/usr/include does not exist and thus
was never resolved by C compiler.
- After commit [0], the line passed to libbpf makefile became:
'<output-dir>/usr/include', this directory exists and is resolved by
C compiler.
- Both 'tools/include' and 'usr/include' define files err.h and types.h.
- libbpf expects headers like 'linux/err.h' and 'linux/types.h'
defined in 'tools/include', not 'usr/include', hence the compilation
error.
This commit removes unnecessary -I flags from libbpf compilation.
(libbpf sets up the necessary includes at lib/bpf/Makefile:63).
Changes v1 [1] -> v2:
- dropped unnecessary replacement of KBUILD_OUTPUT with $(objtree)
(Andrii)
Changes v2 [2] -> v3:
- make sure --sysroot option is set for libbpf's EXTRA_CFLAGS,
if $(SYSROOT) is set (Stanislav)
[0] commit
|
||
|---|---|---|
| .. | ||
| acrn | ||
| auxdisplay | ||
| binderfs | ||
| bpf | ||
| cgroup | ||
| configfs | ||
| connector | ||
| coresight | ||
| fanotify | ||
| fprobe | ||
| ftrace | ||
| hid | ||
| hidraw | ||
| hw_breakpoint | ||
| kdb | ||
| kfifo | ||
| kmemleak | ||
| kobject | ||
| kprobes | ||
| landlock | ||
| livepatch | ||
| mei | ||
| nitro_enclaves | ||
| pfsm | ||
| pidfd | ||
| pktgen | ||
| qmi | ||
| rpmsg | ||
| rust | ||
| seccomp | ||
| timers | ||
| trace_events | ||
| trace_printk | ||
| uhid | ||
| user_events | ||
| v4l | ||
| vfio-mdev | ||
| vfs | ||
| watch_queue | ||
| watchdog | ||
| Kconfig | ||
| Makefile | ||