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1 Commits

Author SHA1 Message Date
Jordan Rose dc352bb82b [analyzer] Check for code testing a variable for 0 after using it as a denominator.
This new checker, alpha.core.TestAfterDivZero, catches issues like this:

  int sum = ...
  int avg = sum / count; // potential division by zero...
  if (count == 0) { ... } // ...caught here

Because the analyzer does not necessarily explore /all/ paths through a program,
this check is restricted to only work on zero checks that immediately follow a
division operation (/ % /= %=). This could later be expanded to handle checks
dominated by a division operation but not necessarily in the same CFG block.

Patch by Anders Rönnholm! (with very minor modifications by me)

llvm-svn: 212731
2014-07-10 16:10:52 +00:00