This is the mail archive of the glibc-bugs@sourceware.org mailing list for the glibc project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

[Bug math/16701] New: [powerpc] optimized ceill implementation for powerpc64 return wrong results


https://sourceware.org/bugzilla/show_bug.cgi?id=16701

            Bug ID: 16701
           Summary: [powerpc] optimized ceill implementation for powerpc64
                    return wrong results
           Product: glibc
           Version: 2.19
            Status: NEW
          Severity: normal
          Priority: P2
         Component: math
          Assignee: unassigned at sourceware dot org
          Reporter: azanella at linux dot vnet.ibm.com

Similar to BZ#16414, the optimized ceill implementation shows some wrong
results depending on the input. Also Checking on implementation comments and
history, I am very confident the assembly implementation was based on a version
before commit 5c68d401698a58cf7da150d9cce769fa6679ba5f that fixes BZ#2423
(Errors in
long double (ldbl-128ibm) rounding functions in glibc-2.4), since the
implementation indeed does not handle some inputs correctly.

Some input that result in wrong values are:

34503599627370498.515625
1192568192774434123539907640624.484375
-34503599627370498.515625
-1192568192774434123539907640624.484375

A straightforward fix is just remove the wrong optimized implementation.

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


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]