git: e626fa022361 - stable/15 - libc/amd64: Disable baseline version of stpncpy()

From: Robert Clausecker <fuz_at_FreeBSD.org>
Date: Sun, 04 Jan 2026 13:24:00 UTC
The branch stable/15 has been updated by fuz:

URL: https://cgit.FreeBSD.org/src/commit/?id=e626fa022361bca98bba93842afb3d749427b801

commit e626fa022361bca98bba93842afb3d749427b801
Author:     Dag-Erling Smørgrav <des@FreeBSD.org>
AuthorDate: 2025-12-16 19:04:51 +0000
Commit:     Robert Clausecker <fuz@FreeBSD.org>
CommitDate: 2026-01-04 13:22:50 +0000

    libc/amd64: Disable baseline version of stpncpy()
    
    This implementation appears to be broken on some CPUs.  Disable it
    until the issue can be investigated and fixed.
    
    PR:             291720
    Fixes:          66eb78377bf1 ("libc/amd64: fix overread conditions in stpncpy()")
    Fixes:          90253d49db09 ("lib/libc/amd64/string: add stpncpy scalar, baseline implementation")
    (cherry picked from commit ce9557d4ee174267504a63b2c8f6009be27368c9)
---
 lib/libc/amd64/string/stpncpy.S | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/libc/amd64/string/stpncpy.S b/lib/libc/amd64/string/stpncpy.S
index df22bb9f0c53..764ee1d4008c 100644
--- a/lib/libc/amd64/string/stpncpy.S
+++ b/lib/libc/amd64/string/stpncpy.S
@@ -36,7 +36,9 @@
 	.set stpncpy, __stpncpy
 ARCHFUNCS(__stpncpy)
 	ARCHFUNC(__stpncpy, scalar)
+#if 0 /* temporarily disabled cf. PR 291720 */
 	ARCHFUNC(__stpncpy, baseline)
+#endif
 ENDARCHFUNCS(__stpncpy)
 
 ARCHENTRY(__stpncpy, scalar)