Fix some shadow variables, including one in file_id.cc that causes all files to generate the same...

Fix some shadow variables, including one in file_id.cc that causes all files to
generate the same hash. Add a test to make sure this doesn't happen again.

committed as r875.

[Mark Mentovai]

Wow.

LGTM

http://breakpad.appspot.com/316002/diff/1/2
File src/client/linux/minidump_writer/minidump_writer.cc (right):

http://breakpad.appspot.com/316002/diff/1/2#newcode674
Line 674: for (unsigned j = 0; j < dumper_.mappings().size(); ++j) {
This is exactly why i and j are terrible name for loop variables.

[Ted Mielczarek]

Ugh. Turns out I found this same bug in my code, and I have a patch for it
sitting in my local patch queue, but I apparently forgot about it.

[Mark Mentovai]

Ted, you said that about another bug in recent memory too. Anything else sitting
in your patch queue we should know about?

[shess]

http://breakpad.appspot.com/316002/diff/1/2
File src/client/linux/minidump_writer/minidump_writer.cc (right):

http://breakpad.appspot.com/316002/diff/1/2#newcode674
Line 674: for (unsigned j = 0; j < dumper_.mappings().size(); ++j) {
On 2011/10/20 13:35:30, Mark Mentovai wrote:
> This is exactly why i and j are terrible name for loop variables.

Is there no compiler willing to provide warnings on this?  Surely the number of
times this is done accidentally grossly outnumbers the legitimate cases.

[Lei Zhang (chromium)]

On 2011/10/20 18:16:59, shess wrote:
> http://breakpad.appspot.com/316002/diff/1/2
> File src/client/linux/minidump_writer/minidump_writer.cc (right):
> 
> http://breakpad.appspot.com/316002/diff/1/2#newcode674
> Line 674: for (unsigned j = 0; j < dumper_.mappings().size(); ++j) {
> On 2011/10/20 13:35:30, Mark Mentovai wrote:
> > This is exactly why i and j are terrible name for loop variables.
> 
> Is there no compiler willing to provide warnings on this?  Surely the number
of
> times this is done accidentally grossly outnumbers the legitimate cases.

-Wshadow will catch these, but it also complains about this pattern, which we
have a lot of.

class Bar {
 public:
  int foo() { return foo_; }
  void set_foo(int foo) { foo_ = foo }; // param shadows a method of this.
 private:
  int foo_;
};