clang/test/Analysis/errno-stdlibraryfunctions-notes.c

   1 // RUN: %clang_analyze_cc1 -verify -analyzer-output text %s \
   2 // RUN:   -analyzer-checker=core \
   3 // RUN:   -analyzer-checker=debug.ExprInspection \
   4 // RUN:   -analyzer-checker=apiModeling.StdCLibraryFunctions \
   5 // RUN:   -analyzer-checker=apiModeling.Errno \
   6 // RUN:   -analyzer-checker=alpha.unix.Errno \
   7 // RUN:   -analyzer-config apiModeling.StdCLibraryFunctions:ModelPOSIX=true
   8
   9 #include "Inputs/errno_var.h"
  10
  11 int access(const char *path, int amode);
  12
  13 void clang_analyzer_warnIfReached();
  14
  15 void test1() {
  16   access("path", 0); // no note here
  17   access("path", 0);
  18   // expected-note@-1{{Assuming that function 'access' is successful, in this case the value 'errno' may be undefined after the call and should not be used}}
  19   if (errno != 0) {
  20     // expected-warning@-1{{An undefined value may be read from 'errno'}}
  21     // expected-note@-2{{An undefined value may be read from 'errno'}}
  22   }
  23 }
  24
  25 void test2() {
  26   if (access("path", 0) == -1) {
  27     // expected-note@-1{{Taking true branch}}
  28     // Failure path.
  29     if (errno != 0) {
  30       // expected-note@-1{{'errno' is not equal to 0}}
  31       // expected-note@-2{{Taking true branch}}
  32       clang_analyzer_warnIfReached(); // expected-note {{REACHABLE}} expected-warning {{REACHABLE}}
  33     } else {
  34       clang_analyzer_warnIfReached(); // no-warning: We are on the failure path.
  35     }
  36   }
  37 }
  38
  39 void test3() {
  40   if (access("path", 0) != -1) {
  41     // Success path.
  42     // expected-note@-2{{Assuming that function 'access' is successful, in this case the value 'errno' may be undefined after the call and should not be used}}
  43     // expected-note@-3{{Taking true branch}}
  44     if (errno != 0) {
  45       // expected-warning@-1{{An undefined value may be read from 'errno'}}
  46       // expected-note@-2{{An undefined value may be read from 'errno'}}
  47     }
  48   }
  49 }