gdb/359: functions return NAN when stepped over if linked to pthread

[tsonicdip at cox dot net]

>Number:         359
>Category:       gdb
>Synopsis:       functions return NAN when stepped over if linked to pthread
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Feb 16 12:48:00 PST 2002
>Closed-Date:
>Last-Modified:
>Originator:     Davy Belk
>Release:        RedHat Linux 5.1-0.71
>Organization:
>Environment:
RedHat Linux 7.1, gcc 2.96 
>Description:
When a simple C++ code is linked to the pthread library, 
and the code is run under gdb, functions that should return
a double return NAN when skipped over using the next command.
Single stepping through or continuing through gives the correct
return value.  An additional oddity is that a string in the 
argument list seems to get lost in the pthread code while single
stepping, but a continue will return and give the correct answer.
>How-To-Repeat:
// > Use the given code:
// Name this file bug.C
// execute the commands:
//   > g++ -g -o bug bug.C -lpthread
//   > gdb bug
// Then use next to step over the call to report
//   to get a return value of NAN.  


#include <string>
#include <iostream>

double report1( const double &x )
{
    return 1.;
}


double report2( const double &x, const string &d )
{
    return 2.;
}

double report3()
{
    return 3.;
}


void main( int argc, char *argv[] )
{
    double x = 5.;
    double x1, x2, x3;
    
    x1 = report1( x );
    cout << "Value: " << x1 << endl;
    
    x2 = report2( x, "Test");
    cout << "Value: " << x2 << endl;
    
    x3 = report3();
    cout << "Value: " << x3 << endl;
    
}
>Fix:
Don't know.
>Release-Note:
>Audit-Trail:
>Unformatted:
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