Potential low hanging fruit from PVS-Studio

[Andrej Mitrovic]

http://www.viva64.com/en/b/0113/
linked from: http://www.reddit.com/r/programming/comments/lhfji/static_analyzer_found_errors_in_chrome_again/

There was this kind of code:

void main()
{
    int x = -1;
    x =- 2;
    assert(x == -3);  // fail
}

This was apparently a typo in the Chrome source code. Perhaps the
compiler could detect this and emit a warning or stop compilation. To
work around it, you would have to add a space immediately after the
equals token if the next token is a minus or plus token. E.g.:

void main()
{
    int x = -1;

    x =-2;    // ng
    x =- 2;   // ng
    x = -2;   // ok
    x = - 2;  // ok

    x =+2;    // ng
    x =+ 2;   // ng
    x = +2;   // ok
    x = + 2;  // ok
}

Alternatively a simple warning could be emitted.

However I don't know if this is a common enough bug to worry about, or
if it could potentially hurt metaprogramming.