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tools/include/linux/types.h: add ulong typedef for musl compatibility

PATCH In review Hisam Mehboob 2 participants 4 messages May 31 – Jun 18

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Hisam Mehboob

author
#0 lore raw

PATCH 1/1 tools/include/linux/types.h: add ulong typedef for musl compatibility

Building KVM selftests with musl libc fails across multiple files (e.g. memslot_perf_test.c, cpuid_test.c) with 'ulong' undeclared.

Under glibc, <semaphore.h> includes <sys/types.h>, which exposes ulong. Under musl, <semaphore.h> includes only <features.h>, <bits/alltypes.h> and <fcntl.h>, and does not include <sys/types.h>. As a result, ulong is not visible through the current selftests include chain.

include/linux/types.h already defines both ulong and ullong in its sysv aliases block. tools/include/linux/types.h mirrors ullong but omits ulong. Add ulong alongside ullong to close the gap.

Signed-off-by Hisam Mehboob <[email protected]>
---
 tools/include/linux/types.h | 1 +
 1 file changed, 1 insertion(+)
tools/include/linux/types.h +1 -0
index d41f8a261bce..ccc90dd4baeb 100644
@@ -42,6 +42,7 @@ typedef __s16 s16;
 typedef __u8  u8;
 typedef __s8  s8;
 
+typedef unsigned long		ulong;
 typedef unsigned long long	ullong;
 
 #ifdef __CHECKER__
Signature · 1 line
2.51.0
AI review
#1 lore raw
Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider: - [Low] Adding `ulong` typedef to `tools/include/linux/types.h` causes a `-Werror=redundant-decls` build…

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] Adding ulong typedef to tools/include/linux/types.h causes a -Werror=redundant-decls build failure in host tools like perf. --

commit 88e8d7a9a4205d14733be0e5978d3a32589a15e0
Author: Hisam Mehboob <[email protected]>

tools/include/linux/types.h: add ulong typedef for musl compatibility

This commit adds a ulong typedef to tools/include/linux/types.h to fix build failures in KVM selftests when using the musl libc.

tools/include/linux/types.h typedef __s16 s16; · line 45

Quoted 9 lines
tools/include/linux/types.h +1 -0
index d41f8a261bce8..ccc90dd4baeb2 100644
@@ -42,6 +42,7 @@ typedef __s16 s16;
 typedef __u8  u8;
 typedef __s8  s8;
 
+typedef unsigned long		ulong;

[Severity: Low]
Will this unconditional typedef cause a build failure in other host tools like perf?

Because glibc and musl <sys/types.h> also provide a ulong typedef, adding this here without guards triggers a -Werror=redundant-decls build failure in tools like perf, which compile with -Wredundant-decls (via EXTRA_WARNINGS in tools/scripts/Makefile.include) alongside -Werror.

Quoted 3 lines
tools/include/linux/types.h +0 -0
 typedef unsigned long long	ullong;
 
 #ifdef __CHECKER__
Signature · 1 line
Sashiko AI review · https://sashiko.dev/#/patchset/[email protected]?part=1
author
#2 lore raw
Quoted 26 lines · On 5/31/26 20:01, [email protected] wrote:

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] Adding ulong typedef to tools/include/linux/types.h causes a -Werror=redundant-decls build failure in host tools like perf. --

commit 88e8d7a9a4205d14733be0e5978d3a32589a15e0
Author: Hisam Mehboob <[email protected]>

tools/include/linux/types.h: add ulong typedef for musl compatibility

This commit adds a ulong typedef to tools/include/linux/types.h to fix build failures in KVM selftests when using the musl libc.

tools/include/linux/types.h typedef __s16 s16; · line 45

Quoted 9 lines
tools/include/linux/types.h +1 -0
index d41f8a261bce8..ccc90dd4baeb2 100644
@@ -42,6 +42,7 @@ typedef __s16 s16;
  typedef __u8  u8;
  typedef __s8  s8;
 
+typedef unsigned long		ulong;

[Severity: Low]
Will this unconditional typedef cause a build failure in other host tools like perf?

Quoted 9 lines

Because glibc and musl <sys/types.h> also provide a ulong typedef, adding this here without guards triggers a -Werror=redundant-decls build failure in tools like perf, which compile with -Wredundant-decls (via EXTRA_WARNINGS in tools/scripts/Makefile.include) alongside -Werror.

Quoted 3 lines
tools/include/linux/types.h +0 -0
  typedef unsigned long long	ullong;
 
  #ifdef __CHECKER__

I couldn't reproduce this. C11 §6.7p3 permits compatible typedef redeclarations, and -Wredundant-decls targets function/object redeclarations, not typedefs.

Happy to hear any feedback on this.

author
#3 lore raw
In reply to Hisam Mehboob
Quoted 2 lines · Hisam Mehboob

Building KVM selftests with musl libc fails across multiple files (e.g. memslot_perf_test.c, cpuid_test.c) with 'ulong' undeclared.

Gentle ping. Could I get some feedback on this patch?

Thanks,
Hisam