Re: [PATCH] tools/build: make in-target rule robust against too long argument error
From: Changqing Li
Date: Tue Mar 03 2026 - 21:36:10 EST
On 3/4/26 06:33, Ian Rogers wrote:
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On Mon, Oct 27, 2025 at 7:16 PM Changqing Li <changqing.li@xxxxxxxxxxxxx> wrote:
Hi, IanSorry Changqing,
Kindly ping. Could you reproduce it? Any comments?
I was reminded by:
https://lore.kernel.org/lkml/20260303211503.165337-1-mmayer@xxxxxxxxxxxx/
that "argument list too long" is a problem for others.
I tried reproducing it, but I think it doesn't fail for me, possibly
because MAX_ARGS is larger on my system:
```
$ xargs --show-limits
Your environment variables take up 6133 bytes
POSIX upper limit on argument length (this system): 2088971
POSIX smallest allowable upper limit on argument length (all systems): 4096
Maximum length of command we could actually use: 2082838
Size of command buffer we are actually using: 131072
Maximum parallelism (--max-procs must be no greater): 2147483647
```
Anyway, the change makes sense to me.
Reviewed-by: Ian Rogers <irogers@xxxxxxxxxx>
Thanks,
Ian
Thanks. I also cannot reproduce with previous length of tmpdir, maybe caused by perf source changes during this period，
but I can still reproduce after I make the tmpdir longer.
$ xargs --show-limits
Your environment variables take up 3124 bytes
POSIX upper limit on argument length (this system): 2091980
POSIX smallest allowable upper limit on argument length (all systems): 4096
Maximum length of command we could actually use: 2088856
Size of command buffer we are actually using: 131072
Maximum parallelism (--max-procs must be no greater): 2147483647
Regards
Changqing
Regards
Changqing
On 8/19/25 11:01, Changqing Li wrote:
On 8/19/25 04:38, Ian Rogers wrote:
CAUTION: This email comes from a non Wind River email account!Hi, Ian
Do not click links or open attachments unless you recognize the
sender and know the content is safe.
On Mon, Jul 28, 2025 at 2:31 AM <changqing.li@xxxxxxxxxxxxx> wrote:
From: Changqing Li <changqing.li@xxxxxxxxxxxxx>Thanks Changqing, the change makes sense to me. The printf is pushing
The command length of in-target scales with the depth of the directory
times the number of objects in the Makefile. When there are many
objects, and O=[absolute_path] is set, and the absolute_path is
relatively long. It is possile that this line "$(call
if_changed,$(host)ld_multi)" will report error:
"make[4]: /bin/sh: Argument list too long"
For example, build perf tools with O=/long/output/path
Like built-in.a and *.mod rules in scripts/Makefile.build, add
$(objpredix)/ by the shell command instead of by Make's builtin
function.
Signed-off-by: Changqing Li <changqing.li@xxxxxxxxxxxxx>
the values into xargs rather than using $^ with ld. I've tried
reproducing the error to test your fix by creating long directory
names in /tmp and then passing them to O=. I've not been able to do
this. Could you send a reproduction for me to test?
Thanks,
Ian
Thanks. Here is my steps:
1. git clone https://github.com/torvalds/linux.git
2. cd linux/tools/perf/
3. mkdir
/tmp/01234567890123456789/0123456789012345678901234567890123456789/0123456789012345678901234567890123456789/012345678901234567890123456789/01234567890123456789/012345678901234567890123456789/01234567890123456789012345678/9012345678901234567890123456789/012345678901234567890123456789/012345678901234567890123456789/01234567890123456789012345678901234567890123456789012345678901234567890123/perf-1.0
4. make NO_LIBTRACEEVENT=1
O=/tmp/01234567890123456789/0123456789012345678901234567890123456789/0123456789012345678901234567890123456789/012345678901234567890123456789/01234567890123456789/012345678901234567890123456789/01234567890123456789012345678/9012345678901234567890123456789/012345678901234567890123456789/012345678901234567890123456789/01234567890123456789012345678901234567890123456789012345678901234567890123/perf-1.0
5. Above step failed with error:
make[4]: /bin/sh: Argument list too long
make[4]: *** [/buildarea2/cli10/tmp/linux/tools/build/Makefile.build
<https://urldefense.com/v3/__http://Makefile.build__;!!AjveYdw8EvQ!c2n7zPX4Vrhwd7a9UxsjCXBGO5V8Llmon1egvupz4kHL4869ilesQgRgQZO8nj8AWwQJUlY9DOoWPD688quA73jNugR6IZRxy09Eig$>:148:
/tmp/01234567890123456789/0123456789012345678901234567890123456789/0123456789012345678901234567890123456789/012345678901234567890123456789/01234567890123456789/012345678901234567890123456789/01234567890123456789012345678/9012345678901234567890123456789/012345678901234567890123456789/012345678901234567890123456789/01234567890123456789012345678901234567890123456789012345678901234567890123/perf-1.0/util/perf-util-in.o]
Error 127
make[3]: *** [/buildarea2/cli10/tmp/linux/tools/build/Makefile.build
<https://urldefense.com/v3/__http://Makefile.build__;!!AjveYdw8EvQ!c2n7zPX4Vrhwd7a9UxsjCXBGO5V8Llmon1egvupz4kHL4869ilesQgRgQZO8nj8AWwQJUlY9DOoWPD688quA73jNugR6IZRxy09Eig$>:142:
util] Error 2
make[2]: *** [Makefile.perf:797:
/tmp/01234567890123456789/0123456789012345678901234567890123456789/0123456789012345678901234567890123456789/012345678901234567890123456789/01234567890123456789/012345678901234567890123456789/01234567890123456789012345678/9012345678901234567890123456789/012345678901234567890123456789/012345678901234567890123456789/01234567890123456789012345678901234567890123456789012345678901234567890123/perf-1.0/perf-util-in.o]
Error 2
Regards
Changqing
---
tools/build/Makefile.build | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/tools/build/Makefile.build b/tools/build/Makefile.build
index 3584ff308607..39066a3ef2fc 100644
--- a/tools/build/Makefile.build
+++ b/tools/build/Makefile.build
@@ -70,11 +70,13 @@ quiet_cmd_gen = GEN $@
# If there's nothing to link, create empty $@ object.
quiet_cmd_ld_multi = LD $@
cmd_ld_multi = $(if $(strip $(obj-y)),\
- $(LD) -r -o $@ $(filter $(obj-y),$^),rm -f
$@; $(AR) rcs $@)
+ printf "$(objprefix)%s " $(patsubst
$(objprefix)%,%,$(filter $(obj-y),$^)) | \
+ xargs $(LD) -r -o $@,rm -f $@; $(AR) rcs $@)
quiet_cmd_host_ld_multi = HOSTLD $@
cmd_host_ld_multi = $(if $(strip $(obj-y)),\
- $(HOSTLD) -r -o $@ $(filter
$(obj-y),$^),rm -f $@; $(HOSTAR) rcs $@)
+ printf "$(objprefix)%s " $(patsubst
$(objprefix)%,%,$(filter $(obj-y),$^)) | \
+ xargs $(HOSTLD) -r -o $@,rm -f $@;
$(HOSTAR) rcs $@)
ifneq ($(filter $(obj),$(hostprogs)),)
host = host_
--
2.34.1