Bug 77678

Summary:	NPTL support witthout TLS
Product:	Gentoo Linux	Reporter:	Jan Kundrát (RETIRED) <jkt>
Component:	[OLD] Core system	Assignee:	Gentoo Toolchain Maintainers <toolchain>
Status:	RESOLVED WONTFIX
Severity:	enhancement
Priority:	High
Version:	unspecified
Hardware:	All
OS:	Linux
Whiteboard:
Package list:		Runtime testing required:	---

Description Jan Kundrát (RETIRED) gentoo-dev

2005-01-12 06:54:15 UTC

hi,
Xen paravitrualisation software (http://xen.sf.net/) has some troubles (slow emulation and even program crashes in some cases with experimantal branches) with applications using Thread Local Storage. Xen's documentation suggests removing /lib/tls directory, but sys-libs/glibc-2.3.4-20040808-r1 doesn't create it, even if it makes use of TLS.
NPTL itself won't cause troubles, AFAIK, so could you introduce new USE flag, "tls", which will make NPTL and TLS independent, or at least allow NPTL without TLS support? Is it technically possible?

AFAIK it could be manually hacked by forcing want_tls() to return 1, but it is ugly and won't survive sync.

Comment 1 SpanKY gentoo-dev

2005-01-12 15:03:18 UTC

glibc-2.3.4.20041102 already does this (nptl / nptlonly)

Comment 2 Jan Kundrát (RETIRED) gentoo-dev

2005-01-16 07:36:19 UTC

so, is there any way to build glibc with both LinuxThreads and NPTL and *without* TLS?

Comment 3 SpanKY gentoo-dev

2005-01-16 11:43:22 UTC

uhh, nptl is tls