clang/test/Analysis/no-return.c

   1 // RUN: %clang_analyze_cc1 -analyzer-checker=core -verify %s
   2
   3 typedef void(fatal_fun)() __attribute__((__noreturn__));
   4 fatal_fun* fatal_fptr;
   5 void fatal_decl() __attribute__((__noreturn__));
   6
   7 int rng();
   8
   9 /// This code calls a [[noreturn]] function pointer, which used to be handled
  10 /// inconsistently between AST builder and CSA.
  11 /// In the result, CSA produces a path where this function returns non-0.
  12 int return_zero_or_abort_by_fnptr() {
  13   if (rng()) fatal_fptr();
  14   return 0;
  15 }
  16
  17 /// This function calls a [[noreturn]] function.
  18 /// If it does return, it always returns 0.
  19 int return_zero_or_abort_by_direct_fun() {
  20   if (rng()) fatal_decl();
  21   return 0;
  22 }
  23
  24 /// Trigger a division by zero issue depending on the return value
  25 /// of the called functions.
  26 int caller() {
  27   int x = 0;
  28   // The following if branches must never be taken.
  29   if (return_zero_or_abort_by_fnptr())
  30     return 1 / x; // no-warning: Dead code.
  31   if (return_zero_or_abort_by_direct_fun())
  32     return 1 / x; // no-warning: Dead code.
  33
  34   // Make sure the warning is still reported when viable.
  35   return 1 / x; // expected-warning {{Division by zero}}
  36 }