* [PATCH v2] selftests/nolibc: fix libc-test with musl libc
@ 2026-03-20 7:00 Thomas Weißschuh
2026-03-20 10:04 ` David Laight
0 siblings, 1 reply; 3+ messages in thread
From: Thomas Weißschuh @ 2026-03-20 7:00 UTC (permalink / raw)
To: Willy Tarreau, Daniel Palmer, David Laight
Cc: linux-kernel, Thomas Weißschuh
Some of the nolibc testcases fail on musl. In these cases nolibc mirrors
the non-standard behavior of glibc.
Avoid the failures by only running these testcases on nolibc and glibc.
Fixes: a5f00be9b3b0 ("tools/nolibc: Add a simple test for writing to a FILE and reading it back")
Fixes: d94393e48c09 ("tools/nolibc/printf: Add support for length modifiers tzqL and formats iX")
Fixes: c2d234d3dc56 ("tools/nolibc/printf: Special case 0 and add support for %#x")
Fixes: 63befd993da4 ("tools/nolibc/printf: Add support for zero padding and field precision")
Fixes: d94393e48c09 ("tools/nolibc/printf: Add support for length modifiers tzqL and formats iX")
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
Changes in v2:
- Also run the affected testcases on glibc.
- Link to v1: https://patch.msgid.link/20260318-nolibc-tests-musl-v1-1-884cd7f48646@weissschuh.net
---
I am thinking about folding the printf fixups directly into the original
patches. Any objections?
---
tools/testing/selftests/nolibc/nolibc-test.c | 20 ++++++++++++++------
1 file changed, 14 insertions(+), 6 deletions(-)
diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c
index 180611aabbfb..4b653172d570 100644
--- a/tools/testing/selftests/nolibc/nolibc-test.c
+++ b/tools/testing/selftests/nolibc/nolibc-test.c
@@ -74,6 +74,14 @@ static const int is_nolibc =
#endif
;
+static const int is_glibc =
+#ifdef __GLIBC__
+ 1
+#else
+ 0
+#endif
+;
+
#if !defined(NOLIBC)
/* Some disabled tests may not compile. */
@@ -867,7 +875,7 @@ int test_file_stream(void)
errno = 0;
r = fwrite("foo", 1, 3, f);
- if (r != 0 || errno != EBADF) {
+ if (r != 0 || ((is_nolibc || is_glibc) && errno != EBADF)) {
fclose(f);
return -1;
}
@@ -1824,13 +1832,13 @@ static int run_printf(int min, int max)
CASE_TEST(hex_alt_prec); EXPECT_VFPRINTF(1, "| 0x02|0x03| 0x123|", "|%#5.2x|%#04x|%#6.2x|", 2, 3, 0x123); break;
CASE_TEST(hex_0_alt); EXPECT_VFPRINTF(1, "|0|0000| 00|", "|%#x|%#04x|%#5.2x|", 0, 0, 0); break;
CASE_TEST(pointer); EXPECT_VFPRINTF(1, "0x1", "%p", (void *) 0x1); break;
- CASE_TEST(pointer_NULL); EXPECT_VFPRINTF(1, "|(nil)|(nil)|", "|%p|%.4p|", (void *)0, (void *)0); break;
- CASE_TEST(string_NULL); EXPECT_VFPRINTF(1, "|(null)||(null)|", "|%s|%.5s|%.6s|", (void *)0, (void *)0, (void *)0); break;
+ CASE_TEST(pointer_NULL); EXPECT_VFPRINTF(is_nolibc || is_glibc, "|(nil)|(nil)|", "|%p|%.4p|", (void *)0, (void *)0); break;
+ CASE_TEST(string_NULL); EXPECT_VFPRINTF(is_nolibc, "|(null)||(null)|", "|%s|%.5s|%.6s|", (void *)0, (void *)0, (void *)0); break;
CASE_TEST(percent); EXPECT_VFPRINTF(1, "a%d42%69%", "a%%d%d%%%d%%", 42, 69); break;
- CASE_TEST(perc_qual); EXPECT_VFPRINTF(1, "a%d2", "a%-14l%d%d", 2); break;
- CASE_TEST(invalid); EXPECT_VFPRINTF(1, "a%12yx3%y42%P", "a%12yx%d%y%d%P", 3, 42); break;
+ CASE_TEST(perc_qual); EXPECT_VFPRINTF(is_nolibc || is_glibc, "a%d2", "a%-14l%d%d", 2); break;
+ CASE_TEST(invalid); EXPECT_VFPRINTF(is_nolibc || is_glibc, "a%12yx3%y42%P", "a%12yx%d%y%d%P", 3, 42); break;
CASE_TEST(intmax_max); EXPECT_VFPRINTF(1, "9223372036854775807", "%lld", ~0ULL >> 1); break;
- CASE_TEST(intmax_min); EXPECT_VFPRINTF(1, "-9223372036854775808", "%Li", (~0ULL >> 1) + 1); break;
+ CASE_TEST(intmax_min); EXPECT_VFPRINTF(is_nolibc || is_glibc, "-9223372036854775808", "%Li", (~0ULL >> 1) + 1); break;
CASE_TEST(uintmax_max); EXPECT_VFPRINTF(1, "18446744073709551615", "%ju", ~0ULL); break;
CASE_TEST(truncation); EXPECT_VFPRINTF(1, "012345678901234567890123456789", "%s", "012345678901234567890123456789"); break;
CASE_TEST(string_width); EXPECT_VFPRINTF(1, " 1", "%10s", "1"); break;
---
base-commit: d59131de97ee69ab4e4b8926089a6e953d699b11
change-id: 20260318-nolibc-tests-musl-61c46f82fbec
Best regards,
--
Thomas Weißschuh <linux@weissschuh.net>
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH v2] selftests/nolibc: fix libc-test with musl libc
2026-03-20 7:00 [PATCH v2] selftests/nolibc: fix libc-test with musl libc Thomas Weißschuh
@ 2026-03-20 10:04 ` David Laight
2026-03-20 17:00 ` Thomas Weißschuh
0 siblings, 1 reply; 3+ messages in thread
From: David Laight @ 2026-03-20 10:04 UTC (permalink / raw)
To: Thomas Weißschuh; +Cc: Willy Tarreau, Daniel Palmer, linux-kernel
On Fri, 20 Mar 2026 08:00:46 +0100
Thomas Weißschuh <linux@weissschuh.net> wrote:
> Some of the nolibc testcases fail on musl. In these cases nolibc mirrors
> the non-standard behavior of glibc.
>
> Avoid the failures by only running these testcases on nolibc and glibc.
>
> Fixes: a5f00be9b3b0 ("tools/nolibc: Add a simple test for writing to a FILE and reading it back")
> Fixes: d94393e48c09 ("tools/nolibc/printf: Add support for length modifiers tzqL and formats iX")
> Fixes: c2d234d3dc56 ("tools/nolibc/printf: Special case 0 and add support for %#x")
> Fixes: 63befd993da4 ("tools/nolibc/printf: Add support for zero padding and field precision")
> Fixes: d94393e48c09 ("tools/nolibc/printf: Add support for length modifiers tzqL and formats iX")
> Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
> ---
> Changes in v2:
> - Also run the affected testcases on glibc.
> - Link to v1: https://patch.msgid.link/20260318-nolibc-tests-musl-v1-1-884cd7f48646@weissschuh.net
> ---
> I am thinking about folding the printf fixups directly into the original
> patches. Any objections?
> ---
> tools/testing/selftests/nolibc/nolibc-test.c | 20 ++++++++++++++------
> 1 file changed, 14 insertions(+), 6 deletions(-)
>
> diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c
> index 180611aabbfb..4b653172d570 100644
> --- a/tools/testing/selftests/nolibc/nolibc-test.c
> +++ b/tools/testing/selftests/nolibc/nolibc-test.c
> @@ -74,6 +74,14 @@ static const int is_nolibc =
> #endif
> ;
>
> +static const int is_glibc =
> +#ifdef __GLIBC__
> + 1
> +#else
> + 0
> +#endif
> +;
> +
> #if !defined(NOLIBC)
> /* Some disabled tests may not compile. */
>
> @@ -867,7 +875,7 @@ int test_file_stream(void)
>
> errno = 0;
> r = fwrite("foo", 1, 3, f);
> - if (r != 0 || errno != EBADF) {
> + if (r != 0 || ((is_nolibc || is_glibc) && errno != EBADF)) {
> fclose(f);
> return -1;
> }
> @@ -1824,13 +1832,13 @@ static int run_printf(int min, int max)
> CASE_TEST(hex_alt_prec); EXPECT_VFPRINTF(1, "| 0x02|0x03| 0x123|", "|%#5.2x|%#04x|%#6.2x|", 2, 3, 0x123); break;
> CASE_TEST(hex_0_alt); EXPECT_VFPRINTF(1, "|0|0000| 00|", "|%#x|%#04x|%#5.2x|", 0, 0, 0); break;
> CASE_TEST(pointer); EXPECT_VFPRINTF(1, "0x1", "%p", (void *) 0x1); break;
> - CASE_TEST(pointer_NULL); EXPECT_VFPRINTF(1, "|(nil)|(nil)|", "|%p|%.4p|", (void *)0, (void *)0); break;
> - CASE_TEST(string_NULL); EXPECT_VFPRINTF(1, "|(null)||(null)|", "|%s|%.5s|%.6s|", (void *)0, (void *)0, (void *)0); break;
> + CASE_TEST(pointer_NULL); EXPECT_VFPRINTF(is_nolibc || is_glibc, "|(nil)|(nil)|", "|%p|%.4p|", (void *)0, (void *)0); break;
> + CASE_TEST(string_NULL); EXPECT_VFPRINTF(is_nolibc, "|(null)||(null)|", "|%s|%.5s|%.6s|", (void *)0, (void *)0, (void *)0); break;
string_NULL should pass on glibc.
> CASE_TEST(percent); EXPECT_VFPRINTF(1, "a%d42%69%", "a%%d%d%%%d%%", 42, 69); break;
> - CASE_TEST(perc_qual); EXPECT_VFPRINTF(1, "a%d2", "a%-14l%d%d", 2); break;
> - CASE_TEST(invalid); EXPECT_VFPRINTF(1, "a%12yx3%y42%P", "a%12yx%d%y%d%P", 3, 42); break;
> + CASE_TEST(perc_qual); EXPECT_VFPRINTF(is_nolibc || is_glibc, "a%d2", "a%-14l%d%d", 2); break;
> + CASE_TEST(invalid); EXPECT_VFPRINTF(is_nolibc || is_glibc, "a%12yx3%y42%P", "a%12yx%d%y%d%P", 3, 42); break;
> CASE_TEST(intmax_max); EXPECT_VFPRINTF(1, "9223372036854775807", "%lld", ~0ULL >> 1); break;
> - CASE_TEST(intmax_min); EXPECT_VFPRINTF(1, "-9223372036854775808", "%Li", (~0ULL >> 1) + 1); break;
> + CASE_TEST(intmax_min); EXPECT_VFPRINTF(is_nolibc || is_glibc, "-9223372036854775808", "%Li", (~0ULL >> 1) + 1); break;
> CASE_TEST(uintmax_max); EXPECT_VFPRINTF(1, "18446744073709551615", "%ju", ~0ULL); break;
> CASE_TEST(truncation); EXPECT_VFPRINTF(1, "012345678901234567890123456789", "%s", "012345678901234567890123456789"); break;
> CASE_TEST(string_width); EXPECT_VFPRINTF(1, " 1", "%10s", "1"); break;
>
> ---
> base-commit: d59131de97ee69ab4e4b8926089a6e953d699b11
> change-id: 20260318-nolibc-tests-musl-61c46f82fbec
>
> Best regards,
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH v2] selftests/nolibc: fix libc-test with musl libc
2026-03-20 10:04 ` David Laight
@ 2026-03-20 17:00 ` Thomas Weißschuh
0 siblings, 0 replies; 3+ messages in thread
From: Thomas Weißschuh @ 2026-03-20 17:00 UTC (permalink / raw)
To: David Laight; +Cc: Willy Tarreau, Daniel Palmer, linux-kernel
On 2026-03-20 10:04:17+0000, David Laight wrote:
> On Fri, 20 Mar 2026 08:00:46 +0100
> Thomas Weißschuh <linux@weissschuh.net> wrote:
>
> > Some of the nolibc testcases fail on musl. In these cases nolibc mirrors
> > the non-standard behavior of glibc.
> >
> > Avoid the failures by only running these testcases on nolibc and glibc.
(...)
> > @@ -1824,13 +1832,13 @@ static int run_printf(int min, int max)
> > CASE_TEST(hex_alt_prec); EXPECT_VFPRINTF(1, "| 0x02|0x03| 0x123|", "|%#5.2x|%#04x|%#6.2x|", 2, 3, 0x123); break;
> > CASE_TEST(hex_0_alt); EXPECT_VFPRINTF(1, "|0|0000| 00|", "|%#x|%#04x|%#5.2x|", 0, 0, 0); break;
> > CASE_TEST(pointer); EXPECT_VFPRINTF(1, "0x1", "%p", (void *) 0x1); break;
> > - CASE_TEST(pointer_NULL); EXPECT_VFPRINTF(1, "|(nil)|(nil)|", "|%p|%.4p|", (void *)0, (void *)0); break;
> > - CASE_TEST(string_NULL); EXPECT_VFPRINTF(1, "|(null)||(null)|", "|%s|%.5s|%.6s|", (void *)0, (void *)0, (void *)0); break;
> > + CASE_TEST(pointer_NULL); EXPECT_VFPRINTF(is_nolibc || is_glibc, "|(nil)|(nil)|", "|%p|%.4p|", (void *)0, (void *)0); break;
> > + CASE_TEST(string_NULL); EXPECT_VFPRINTF(is_nolibc, "|(null)||(null)|", "|%s|%.5s|%.6s|", (void *)0, (void *)0, (void *)0); break;
>
> string_NULL should pass on glibc.
Indeed, now fixed up.
And the whole thing has been pushed to nolibc/for-next.
Thomas
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2026-03-20 17:00 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-03-20 7:00 [PATCH v2] selftests/nolibc: fix libc-test with musl libc Thomas Weißschuh
2026-03-20 10:04 ` David Laight
2026-03-20 17:00 ` Thomas Weißschuh
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox