PR/57881 CVS commit: [netbsd-10] src

["Martin Husemann" <martin%netbsd.org@localhost>]

The following reply was made to PR port-vax/57881; it has been noted by GNATS.

From: "Martin Husemann" <martin%netbsd.org@localhost>
To: gnats-bugs%gnats.NetBSD.org@localhost
Cc: 
Subject: PR/57881 CVS commit: [netbsd-10] src
Date: Wed, 2 Oct 2024 12:46:14 +0000

 Module Name:	src
 Committed By:	martin
 Date:		Wed Oct  2 12:46:13 UTC 2024
 
 Modified Files:
 	src/distrib/sets/lists/debug [netbsd-10]: mi
 	src/distrib/sets/lists/tests [netbsd-10]: mi
 	src/lib/libm/src [netbsd-10]: s_remquo.c
 	src/tests/lib/libm [netbsd-10]: Makefile
 Added Files:
 	src/tests/lib/libm [netbsd-10]: t_remquo.c
 
 Log Message:
 Pull up following revision(s) (requested by gdt in ticket #912):
 
 	distrib/sets/lists/debug/mi: revision 1.449
 	lib/libm/src/s_remquo.c: revision 1.3
 	lib/libm/src/s_remquo.c: revision 1.4
 	distrib/sets/lists/tests/mi: revision 1.1339
 	tests/lib/libm/t_remquo.c: revision 1.1
 	tests/lib/libm/t_remquo.c: revision 1.2
 	tests/lib/libm/Makefile: revision 1.51
 
 tests: Add test for remquo
 
 This test currently fails, because remquo has bugs.  (A bugfix will be
 committed soon.)  Test vectors derived from results from code by
 Charles Karney in GeodesicLib/proj, and manually inspected.
 
 t_remquo: Work around missing remquo(3) for vax
 Part of PR port-vax/57881
 
 libm/remquo: Fix bug where wrong quotient was returned
 
 Fix taken from FreeBSD:
   https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=166463
   https://cgit.freebsd.org/src/commit/lib/msun/src/s_remquo.c?id=1cbd288942b08217e99bf889e0967895d53af00c
 
 FreeBSD commit message:
   Fix a bug in remquo{,f,l}, in which the quotient didn't always have the
   correct sign when the remainder was 0.
   Fix a separate bug in remquo alone, in which the remainder and
   quotient were both off by a bit in certain cases involving subnormal
   remainders.
   The bugs affected all platforms except amd64 and i386, on which the
   routines are implemented in assembly.
 
 (On NetBSD, this bug manifests on amd64.)
 
 libm/remquo: Fix bug where remquo returned wrong sign of quo
 ISO C requires that quo be congruent to the quotient mod 2^k and have
 a particular sign.  The current code can return 0 when it should be
 negative.
 Because the code chooses k=31 (for the requirement of congruence
 modulo 2^k), the only value available (in ILP32 or LP64) that is
 negative and congruent to 0 is 0x80000000.  In the specific case of
 wanting "-0", return 0x80000000.
 Resolves t_remquo test failure.
 
 
 To generate a diff of this commit:
 cvs rdiff -u -r1.394.2.9 -r1.394.2.10 src/distrib/sets/lists/debug/mi
 cvs rdiff -u -r1.1238.2.11 -r1.1238.2.12 src/distrib/sets/lists/tests/mi
 cvs rdiff -u -r1.1 -r1.1.56.1 src/lib/libm/src/s_remquo.c
 cvs rdiff -u -r1.48 -r1.48.2.1 src/tests/lib/libm/Makefile
 cvs rdiff -u -r0 -r1.2.2.2 src/tests/lib/libm/t_remquo.c
 
 Please note that diffs are not public domain; they are subject to the
 copyright notices on the relevant files.