[bug #59913] gsl 2.3.0 problem in gsl_integration_cquad

[Patrick Alken]

URL:
  <https://savannah.gnu.org/bugs/?59913>

                 Summary: gsl 2.3.0 problem in gsl_integration_cquad
                 Project: GNU Scientific Library
            Submitted by: psa
            Submitted on: Wed 20 Jan 2021 02:41:50 AM UTC
                Category: None
                Severity: 3 - Normal
        Operating System: 
                  Status: None
             Assigned to: None
             Open/Closed: Open
                 Release: 
         Discussion Lock: Any

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Details:

from buchholz =at= tugraz =dot= at

I found a problem in gsl (assuming the compiler/linker is not broken), which I
would consider a bug.

A minimal working example is attached.
I compiled using g++ 6.3.0 and gsl 2.3.0. The compile command is given in the
file.
The code uses an extension to cause the code to stop on floating point
exceptions (found this via stack exchange
https://linux.die.net/man/3/feenableexcept).

I would expect the code to just run through with output something like

result: 4.39016e-164
abserr: 0
nevals: 33

Instead i get the message

Gleitkomma-Ausnahme (german for floating point exception)

Running the program with gdb I get

Program received signal SIGFPE, Arithmetic exception.
0x00007ffff7a1b42f in gsl_integration_cquad () from
/usr/lib/x86_64-linux-gnu/libgsl.so.19
(gdb) backtrace
#0  0x00007ffff7a1b42f in gsl_integration_cquad () from
/usr/lib/x86_64-linux-gnu/libgsl.so.19
#1  0x0000555555554cee in main () at main.cpp:42


Changing the lower bound to 19.2 will cause the code to work, i.e. no floating
point exception.

If I do not trap the exception the code works as expected, but if there is no
real problem, then no exception should be raised.






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File Attachments:


-------------------------------------------------------
Date: Wed 20 Jan 2021 02:41:50 AM UTC  Name: main.cpp  Size: 1KiB   By: psa

<http://savannah.gnu.org/bugs/download.php?file_id=50749>

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