Experimental Physics and
Industrial Control System

[email protected] (Norm Hill) · Wed, 16 Apr 1997 13:39:02 -0700

Hi,

There is a bug in the sun workshop C++ compiler (version "WorkShop
Compilers 4.2 30 Oct 1996 C++ 4.2") that can effect programs using the
EPICS channel access library.  It should never be possible for the body
of the "if" in the following code to execute, but it will execute if it
is compiled with:

CC -O -I/opt/local/epics/epics/base/include/ main.C

The bug goes away if any of various things in the example are changed,
i.e. if the function is not inline, if the code is compiled with the -g
option, etc.

The bug seems to be triggered by the compiler proecessing the relatively
compilicated expression insterted into the code when the channel access
status macros are expanded.

Norm

----------------------------------------
#include "cadef.h"

#include "stdio.h"

inline void t1( void )
{
    int caStatus = ECA_NORMAL; 
    if ( caStatus != ECA_NORMAL ) 
    { 
        printf( " error, %d\n", ECA_NORMAL);    // never get here.
        return ; 
    }

}
main()
{
    t1();
    printf( "Hello W#include "cadef.h"
}

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System