optimization/5377: Warning not given when optimizing

[booh at altern dot org]

>Number:         5377
>Category:       optimization
>Synopsis:       Warning not given when optimizing
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    unassigned
>State:          open
>Class:          accepts-illegal
>Submitter-Id:   net
>Arrival-Date:   Mon Jan 14 08:26:00 PST 2002
>Closed-Date:
>Last-Modified:
>Originator:     booh@altern.org
>Release:        gcc-3.0.3
>Organization:
>Environment:
i686-pc-linux-gnu
>Description:
Here are the results with some versions, note that
only the latest shows the problem.

gcc-2.95.3 -Wreturn-type -O2 -finline-functions :
In function `function':
warning: control reaches end of non-void function

gcc-3.0.3 -Wreturn-type -O2 :
In function `function':
warning: control reaches end of non-void function
/* ./a.out returns 123. */

gcc-3.0.3 -Wreturn-type -O2 -finline-functions
/* No warning. */


So the problem is that in the last compilation
the warning is not given and the function()
returns nothing.
>How-To-Repeat:
static int global_variable;

static int
function (void)
{
  /* Just for function() to do something. */
  global_variable = 123;
}

int
main (void)
{
  return function ();
}
>Fix:
Maybe check_function_return_warnings() should be called before considering making the function inline.
>Release-Note:
>Audit-Trail:
>Unformatted: