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Date: Sun, 30 Nov 2008 18:52:00 -0000
Subject: [Bug c++/38335]  New: Code warning
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From: "adam dot c dot scott at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
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Add warning about modifying an index in a for loop.

Without this warning the kind of errors introduced in code are likely to be
very difficult to debug (core dump).

Example code to reproduce below.  Current commandline used to compile: -ansi
-pedantic -Wall -O.

#include <iostream>
using namespace std;

int main(int argc, char** argv) {
    int loopndx;
    int indexes[10];

    for( loopndx=0 ; loopndx <=10 ; loopndx++) {
        if (loopndx==5) {
            loopndx=666666;
        }
        cout << indexes[loopndx];
    }
    return (EXIT_SUCCESS);
}


-- 
           Summary: Code warning
           Product: gcc
           Version: 3.4.4
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: adam dot c dot scott at gmail dot com
 GCC build triplet: dmd
  GCC host triplet: cyg
GCC target triplet: gdc


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38335