From nobody Sun Jan 28 05:22:59 2024 X-Original-To: freebsd-current@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4TN0FS62tSz57mfq for ; Sun, 28 Jan 2024 05:23:08 +0000 (UTC) (envelope-from sgk@troutmask.apl.washington.edu) Received: from troutmask.apl.washington.edu (troutmask.apl.washington.edu [128.95.76.21]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4TN0FR4dVGz43F7; Sun, 28 Jan 2024 05:23:06 +0000 (UTC) (envelope-from sgk@troutmask.apl.washington.edu) Authentication-Results: mx1.freebsd.org; none Received: from troutmask.apl.washington.edu (localhost [127.0.0.1]) by troutmask.apl.washington.edu (8.17.1/8.17.1) with ESMTP id 40S5Mxon067649; Sat, 27 Jan 2024 21:22:59 -0800 (PST) (envelope-from sgk@troutmask.apl.washington.edu) DKIM-Filter: OpenDKIM Filter v2.10.3 troutmask.apl.washington.edu 40S5Mxon067649 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=troutmask.apl.washington.edu; s=troutmask; t=1706419379; bh=UgvBIwlQmQn2feX46ZfW1XF3WNc9lTdMxp6DPyHPN6c=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To:From; b=KM91RIfJ0dAiTshmOVyxuC+CN0VL2Ql/DbRojG6fkgQfHVMZNtihahOUoZJTg5JJm tnQCIWpQgpNUA2zdRFyJ3Pb57OIUeTYUNixD6ss84n6XtoPU6j4uMbRgNhNIT1IbsS eDf9cW3QMY5h7YsCuDk5pcHtZqxK6zoJxq3ecVKBQZr/XlVIcLFyrQ2xOPewoU5XZ/ errCTOHNOa7Uv5CCFFjL3wvMDb5848qOo81ygEgWsfYUvOrUjmg8V1aGb0v7ron/xb 7Kd4kp5EdywHn7T0S+TdNM62J4Cd5HE/dHxYHgcFgwC6gPko+ifPNhXs3gYPmLdHxO dvrtNvLJIPH5w== Received: (from sgk@localhost) by troutmask.apl.washington.edu (8.17.1/8.17.1/Submit) id 40S5Mx7G067648; Sat, 27 Jan 2024 21:22:59 -0800 (PST) (envelope-from sgk) Date: Sat, 27 Jan 2024 21:22:59 -0800 From: Steve Kargl To: Dimitry Andric Cc: FreeBSD CURRENT Subject: Re: llvm ld vs binutils ld Message-ID: Reply-To: sgk@troutmask.apl.washington.edu References: List-Id: Discussions about the use of FreeBSD-current List-Archive: https://lists.freebsd.org/archives/freebsd-current List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-current@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: 4TN0FR4dVGz43F7 X-Spamd-Bar: ---- X-Rspamd-Pre-Result: action=no action; module=replies; Message is reply to one we originated X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[]; ASN(0.00)[asn:73, ipnet:128.95.0.0/16, country:US] On Sat, Jan 27, 2024 at 10:29:34PM +0100, Dimitry Andric wrote: > On 27 Jan 2024, at 18:08, Steve Kargl wrote: > > > > In an attempt to cleanup a bit of src/lib/msun, I ran into > > a small issue that I cannot explain at the moment. If I have > > /usr/bin/ld in my path prior to /usr/local/bin/ld everything > > works > > > > % which ld > > /usr/bin/ld > > % make clean && make cleandepend > > % make > > > > and I have a libm.so.5. But if /usr/local/bin/ld is found, I > > see > > > > % cd msun > > % make clean && make cleandepend > > % make > > .. > > ld: error: version script assignment of 'FBSD_1.0' to symbol 'fabs' \ > > failed: symbol not defined > > cc: error: linker command failed with exit code 1 (use -v to see invocation) > > *** Error code 1 > > > > Stop. > > make: stopped in /usr/src/lib/msun > > > > % grep fabs /usr/src/lib/msun/Symbol.map > > fabs; > > fabsf; > > fabsl; > > > > But, if one looks in msun/Makefile, one see > > > > # FreeBSD's C library supplies these functions: > > #COMMON_SRCS+= s_fabs.c s_frexp.c s_isnan.c s_ldexp.c s_modf.c > > > > so fabs is not built with libm. > > > > % nm --dynamic /lib/libc.so.7 | grep fabs > > 00000000000ba600 T fabs > > % nm --dynamic /lib/libm.so.5 | grep fabs > > 000000000001fa90 T fabsf > > 00000000000252e0 T fabsl > > > > > > Is this a known issue? Should fabs be removed from Symbol.map? > > Yes, fabs is excluded in msun's Makefile: > > # FreeBSD's C library supplies these functions: > #COMMON_SRCS+= s_fabs.c s_frexp.c s_isnan.c s_ldexp.c s_modf.c Thanks for the quick response. I knew this, but > so it should not have been in Symbol.map at all. it has been this way for a very long time. > The comment is also > incorrect, since s_frexp.c and s_isnan.c *are* actually in COMMON_SRCS, > see lines 79 and 80 of the Makefile. (They are indeed also in libc, so > which one is chosen is only known by the linker. :) I would it depends on the search order of the libraries. For static linking, it's the order on the commandline. For rtld, it's the order of the libraries in the cache. % nm --dynamic /lib/libc.so.7 | grep snan 00000000000ace30 T __isnan@@FBSD_1.0 00000000000ace60 T __isnanf@@FBSD_1.0 00000000000ace30 W isnan@@FBSD_1.0 00000000000ace60 W isnanf@@FBSD_1.0 % nm --dynamic /lib/libm.so.5 | grep snan 00000000000220a0 T __isnanf@@FBSD_1.2 00000000000220d0 T __isnanl@@FBSD_1.0 00000000000220a0 W isnanf@@FBSD_1.0 Not quite. isnan is in libc but libm. isnanf seems to be in both, and isnanl is only in libm. Does FBSD_1.2 trump FBSD_1.0 for __isnanf? > It doesn't complain with lld >= 16 because of > https://cgit.freebsd.org/src/commit/?id=2ba84b4bcdd60, where it add > -Wl,--undefined-version to suppress such warnings. I added that rather > big hammer to be able to continue importing llvm 16, but I see now that > it may be better to attempt to fix all individual failures due to > missing symbols. > > The reason that it still goes wrong if you put /usr/local/bin in front > of your PATH (or if you set LD explicitly to /usr/local/bin/ld) is that > /usr/bin/cc will pick /usr/bin/ld over whatever it finds in the PATH or > in the LD variable, while bsd.linker.mk still uses PATH or LD to find > the linker type and version. E.g., it concludes that the linker type is > BFD and the version is 2.40, then does not add the > -Wl,--undefined-version to allow undefined symbols. Thanks for the details. This had me stumped. -- Steve