[perl #46225] [PATCH] Remove passing possible negative index to array in src/pmc.c (Coverity CID 22)

[via RT]

# New Ticket Created by  Paul Cochrane 
# Please include the string:  [perl #46225]
# in the subject line of all future correspondence about this issue. 
# <URL: http://rt.perl.org/rt3/Ticket/Display.html?id=46225 >


In Coverity CID 22 there is a warning about potentially passing a
negative index to an array.  The attached patch corrects the issue,
and 'make test' passes.  If noone complains I'll apply the patch in
about 3 days, or if approved, as soon as I can.

Paul

Files affected: src/pmc.c

Index: src/pmc.c
===================================================================
--- src/pmc.c   (revision 21951)
+++ src/pmc.c   (working copy)
@@ -380,9 +380,16 @@
         return type;
     }
     if (type < enum_type_undef) {
-        real_exception(interp, NULL, 1, "native type with name '%s' already 
exists - "
-                "can't register PMC", data_types[type].name);
-        return 0;
+        char *type_name;
+        if (type < 0) {
+            strcpy(type_name, "undefined type");
+        }
+        else {
+            strcpy(type_name, data_types[type].name);
+        }
+        real_exception(interp, NULL, 1,
+                "native type with name '%s' already exists - "
+                "can't register PMC", type_name);
     }

     classname_hash = interp->class_hash;