Bug 1025744

Summary: pkg-config doesn't show tinfo link flag for ncurses
Product: Red Hat Enterprise Linux 6 Reporter: Deepu K S <dkochuka>
Component: ncursesAssignee: Miroslav Lichvar <mlichvar>
Status: CLOSED ERRATA QA Contact: Martin Frodl <mfrodl>
Severity: medium Docs Contact:
Priority: medium    
Version: 6.4CC: chantry.xavier, cww, dkochuka, dkutalek, gregory.0xf0, mfrodl, mlichvar, ovasik, philwyett.vendetta
Target Milestone: rc   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: ncurses-5.7-4.20090207.el6 Doc Type: Bug Fix
Doc Text:
Cause: The ncurses pc (pkg-config) files didn't include -ltinfo for static linking with ncurses. Consequence: Compilation of applications that use pkg-config and static linking could fail. Fix: Include -ltinfo in the pkg-config files Result: Applications compile successfully.
 Story Points: ---
Clone Of: Environment:
Last Closed: 2015-03-16 08:40:11 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 947782, 1075802, 1159825    
Attachments:
Description Flags
ncurses.pc file with tinfo added none

Description Deepu K S 2013-11-01 12:27:56 UTC 
Description of problem:
pkg-config returns incorrect results for ncurses (missing tinfo dependency)

'pkg-config --libs --static ncurses' doesn't return the tinfo link flag values. Doing an objdump or ldd to the libncurses.so library returns the libtinfo library.

# objdump -x /usr/lib64/libncurses.so | grep NEEDED
  NEEDED               libc.so.6
  NEEDED               libdl.so.2
  NEEDED               libtinfo.so.5

At present, below is the output for pkg-config.
Actual results:
$ /usr/bin/pkg-config --libs --static ncurses
-lncurses  
$ /usr/bin/pkg-config --libs --static ncursesw
-lncursesw

Expected results:
The pkg-config entry should be changed to require tinfo. We need to add tinfo to Requires: field in ncurses.pc and ncursesw.pc

$ /usr/bin/pkg-config --libs --static ncurses
-lncurses -ltinfo
$ /usr/bin/pkg-config --libs --static ncursesw
-lncursesw -ltinfo

Version-Release number of selected component (if applicable):
Red Hat Enterprise Linux 6
ncurses-5.7-3.20090208.el6.x86_64
ncurses-devel-5.7-3.20090208.el6.x86_64
Comment 1 Deepu K S 2013-11-01 12:33:58 UTC 
Created attachment 818281 [details]
ncurses.pc file with tinfo added
Comment 3 RHEL Program Management 2013-11-01 12:50:17 UTC 
This request was evaluated by Red Hat Product Management for
inclusion in the current release of Red Hat Enterprise Linux.
Because the affected component is not scheduled to be updated
in the current release, Red Hat is unable to address this
request at this time.

Red Hat invites you to ask your support representative to
propose this request, if appropriate, in the next release of
Red Hat Enterprise Linux.
Comment 5 Miroslav Lichvar 2014-01-02 10:53:45 UTC 
Yes, with static linking -ltinfo should be included in the list. But it needs to be in requires.private so it's not listed when using dynamic linking. I.e.

Requires.private: tinfo
Comment 11 errata-xmlrpc 2015-03-16 08:40:11 UTC 
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHBA-2015-0687.html
Comment 12 Xavier 2015-10-15 13:39:19 UTC 
If "pkg-config --libs ncurses" returns only "-lncurses", and the linker flags --no-add-needed is used, don't we have a problem ?
If I understood correctly, the --no-add-needed flag even became the default in redhat 7.

And when using clang, which invokes directly the linker, the --no-add-needed flag is always added as soon as we are on a redhat system (c.f. https://llvm.org/bugs/show_bug.cgi?id=19745)

And on debian "pkg-config --libs ncurses" returns "-lncurses -ltinfo".

That said, I guess I can use "pkg-config --libs ncurses tinfo" instead, centos 5 did not have a pkgconfig file anyway, and this will work on redhat >= 6 and on debian.
Comment 13 Miroslav Lichvar 2015-10-15 15:28:20 UTC 
I think that depends on the application. If it uses the libtinfo symbols, it should use pkg-config to get the tinfo libs and don't expect it will be included in the ncurses libs.