https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83553
Bug ID: 83553
Summary: compiler removes body of the for-loop, although there
is a case label inside
Product: gcc
Version: 7.2.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: jan.dethlefs at arcor dot de
Target Milestone: ---
Created attachment 42952
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=42952&action=edit
C++ source code
It seems that the complier removes the body of the for-loop completely.
Obviously, because there is a constant condition that is always false.
But I think this behaviour is wrong, because there is a valid case-label inside
the body.
The following is not working anymore.
int f2(int n)
{
printf("f2(%d)\n", n);
int x=n;
switch(x){
case 0:
for( x=0; false; printf("for-expression\n")){
case 2:
printf("case 2-statement\n");
}
}
return x;
}
In Version 7.2.1. the statement for case 2 and the for-expression are not
executed.
Output>
f2(0)
f2(2)
In Version 4.8.5. the code works as expected.
Output>
f2(0)
f2(2)
case 2-statement
for-expression
