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digitalmars.D.bugs - [Issue 4158] New: switch segfault

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=4158

           Summary: switch segfault
           Product: D
           Version: unspecified
          Platform: Other
        OS/Version: Linux
            Status: NEW
          Severity: major
          Priority: P2
         Component: DMD
        AssignedTo: nobody puremagic.com
        ReportedBy: k-foley onu.edu



DMD 2.045

int main(string[] args)
{
    //switch (0) { } // segfaults
    switch (0) { case 0: }
    //switch (0) { case 1: } // segfaults
    switch (0) { case 1: default: }
    switch (0) { default: }

    return 0;
}

---

Seems to segfault when none of the labels inside the switch are jumped to.

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May 04 2010
next sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=4158


Walter Bright <bugzilla digitalmars.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
                 CC|                            |bugzilla digitalmars.com
         Resolution|                            |INVALID



23:44:21 PDT ---
It doesn't actually segfault, it executes a HALT instruction. If there is no
default in a switch, the compiler inserts one of the form:

  default: HALT

The idea is that the default should not be implied as fall-through, which it
does in C.

D is behaving as it is designed to.

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prev sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=4158






 It doesn't actually segfault, it executes a HALT instruction. If there is no
 default in a switch, the compiler inserts one of the form:
 
   default: HALT
 
 The idea is that the default should not be implied as fall-through, which it
 does in C.
 
 D is behaving as it is designed to.


http://digitalmars.com/d/2.0/statement.html#SwitchStatement

"If none of the case expressions match, and there is not a default statement, a
std.switcherr.SwitchError is thrown. The reason for this is to catch the common
programming error of adding a new value to an enum, but failing to account for
the extra value in switch statements. This behavior is unlike C or C++."

Should sync this with the docs.

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May 05 2010