git: d7b3f3c84e68 - stable/13 - libc: Fix build on case-insensitive file systems

From: Jessica Clarke <jrtc27_at_FreeBSD.org>
Date: Sun, 10 Oct 2021 13:38:11 UTC
The branch stable/13 has been updated by jrtc27:

URL: https://cgit.FreeBSD.org/src/commit/?id=d7b3f3c84e684a613b175624cb04d51f49c0a731

commit d7b3f3c84e684a613b175624cb04d51f49c0a731
Author:     Jessica Clarke <jrtc27@FreeBSD.org>
AuthorDate: 2021-09-10 00:19:38 +0000
Commit:     Jessica Clarke <jrtc27@FreeBSD.org>
CommitDate: 2021-10-10 13:33:52 +0000

    libc: Fix build on case-insensitive file systems
    
    On case-insensitive file systems (most likely to be seen on macOS, where
    it is the default), _Fork.o for the new POSIX _Fork function conflicts
    with _fork.o for the PSEUDO file. This results in non-determinsitic
    behaviour in terms of which ends up being present; if _Fork.o wins then
    the build fails to link libc.so due to missing __sys_fork, and if
    _fork.o wins then libc silently fails to include the implementation of
    _Fork. A similar issue occurred in the past for C99's _Exit conflicting
    with exit(2) and was fixed in cb1cb6a2a83f, so this adds a fix based on
    that.
    
    As a longer-term solution it might be better to instead make the
    generated files use a different prefix that's less likely to conflict
    with other things (such as __sys_foo.o given they always contain that)
    but that's a rather more invasive change.
    
    Fixes:  49ad342cc10c ("Add _Fork()")
    Reviewed by:    kib
    MFC after:      1 week
    Differential Revision:  https://reviews.freebsd.org/D31895
    
    (cherry picked from commit 877175a17a0a5da3f4f43ca9f38adb04042f4cf5)
---
 lib/libc/sys/Makefile.inc                | 2 +-
 lib/libc/sys/{_Fork.c => POSIX2x_Fork.c} | 0
 2 files changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/libc/sys/Makefile.inc b/lib/libc/sys/Makefile.inc
index d0fd7bda74f5..d2b39fe65c44 100644
--- a/lib/libc/sys/Makefile.inc
+++ b/lib/libc/sys/Makefile.inc
@@ -49,7 +49,7 @@ SRCS+= closefrom.c
 SRCS+= pipe.c
 SRCS+= shm_open.c
 SRCS+= vadvise.c
-SRCS+= _Fork.c
+SRCS+= POSIX2x_Fork.c
 
 SRCS+=	compat-stub.c
 
diff --git a/lib/libc/sys/_Fork.c b/lib/libc/sys/POSIX2x_Fork.c
similarity index 100%
rename from lib/libc/sys/_Fork.c
rename to lib/libc/sys/POSIX2x_Fork.c