[Bug math/6796] fdim() does not set errno on overflow

[Bug math/6796] fdim() does not set errno on overflow

[jsm28 at gcc dot gnu.org]

http://sourceware.org/bugzilla/show_bug.cgi?id=6796

Joseph Myers <jsm28 at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|aj at suse dot de           |unassigned at sourceware
                   |                            |dot org

--- Comment #2 from Joseph Myers <jsm28 at gcc dot gnu.org> 2012-03-01 16:36:39 UTC ---
Confirmed with current sources on x86.  x86_64 sets errno correctly.

-- 
Configure bugmail: http://sourceware.org/bugzilla/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are on the CC list for the bug.

[Bug math/6796] fdim() does not set errno on overflow

[polacek at redhat dot com]

http://sourceware.org/bugzilla/show_bug.cgi?id=6796

Marek Polacek <polacek at redhat dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |polacek at redhat dot com

-- 
Configure bugmail: http://sourceware.org/bugzilla/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are on the CC list for the bug.

[Bug math/6796] fdim() does not set errno on overflow

[mtk.manpages at gmail dot com]

https://sourceware.org/bugzilla/show_bug.cgi?id=6796

--- Comment #6 from Michael Kerrisk <mtk.manpages at gmail dot com> ---
Fix documented for man-pages-5.07

commit b36801ebb7ab8e7f9dc6e7f028280ee24a42ab07
Author: Michael Kerrisk <mtk.manpages@gmail.com>
Date:   Sat May 23 12:01:15 2020 +0200

    fdim.3: BUGS: these functions did not set errno on some architectures

    The bug was fixed in glibc 2.24.
    https://www.sourceware.org/bugzilla/show_bug.cgi?id=6796

    Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>

diff --git a/man3/fdim.3 b/man3/fdim.3
index 4e70fee75..f15312978 100644
--- a/man3/fdim.3
+++ b/man3/fdim.3
@@ -61,17 +61,13 @@ when calling these functions.
 The following errors can occur:
 .TP
 Range error: result overflow
-.\" .I errno
-.\" is set to
-.\" .BR ERANGE .
+.I errno
+is set to
+.BR ERANGE .
 An overflow floating-point exception
 .RB ( FE_OVERFLOW )
 is raised.
 .PP
-These functions do not set
-.IR errno .
-.\" FIXME . Is it intentional that these functions do not set errno?
-.\" Bug raised: http://sources.redhat.com/bugzilla/show_bug.cgi?id=6796
 .SH VERSIONS
 These functions first appeared in glibc in version 2.1.
 .SH ATTRIBUTES
@@ -90,5 +86,11 @@ T}   Thread safety   MT-Safe
 .TE
 .SH CONFORMING TO
 C99, POSIX.1-2001, POSIX.1-2008.
+.SH BUGS
+Before glibc version 2.24
+.\" https://www.sourceware.org/bugzilla/show_bug.cgi?id=6796
+on certain architectures (e.g., x86, but not x86_64)
+these functions did not set
+.IR errno .
 .SH SEE ALSO
 .BR fmax (3)

-- 
You are receiving this mail because:
You are on the CC list for the bug.

[Bug math/6796] fdim() does not set errno on overflow

[mtk dot manpages at gmail dot com]

------- Additional Comments From mtk dot manpages at gmail dot com  2008-07-31 10:07 -------
Created an attachment (id=2858)
 --> (http://sourceware.org/bugzilla/attachment.cgi?id=2858&action=view)
test program

Sample run demonstrating the problem

$ /tmp/mt_fdim -- dbl_max -dbl_max
errno == 0
fetestexcept() says:  FE_OVERFLOW FE_INEXACT
fdim(1.79769313486231571e+308,-1.79769313486231571e+308)=inf
0 FE_OVERFLOW +inf


-- 


http://sourceware.org/bugzilla/show_bug.cgi?id=6796

------- You are receiving this mail because: -------
You are on the CC list for the bug, or are watching someone who is.