clang/test/SemaCXX/warn-missing-variable-declarations.cpp

   1 // RUN: %clang_cc1 -fsyntax-only -verify -Wmissing-variable-declarations -std=c++17 %s
   2
   3 // Variable declarations that should trigger a warning.
   4 int vbad1; // expected-warning{{no previous extern declaration for non-static variable 'vbad1'}}
   5 // expected-note@-1{{declare 'static' if the variable is not intended to be used outside of this translation unit}}
   6
   7 int vbad2 = 10; // expected-warning{{no previous extern declaration for non-static variable 'vbad2'}}
   8 // expected-note@-1{{declare 'static' if the variable is not intended to be used outside of this translation unit}}
   9
  10 namespace x {
  11   int vbad3; // expected-warning{{no previous extern declaration for non-static variable 'vbad3'}}
  12   // expected-note@-1{{declare 'static' if the variable is not intended to be used outside of this translation unit}}
  13 }
  14
  15 // Variable declarations that should not trigger a warning.
  16 static int vgood1;
  17 extern int vgood2;
  18 int vgood2;
  19 static struct {
  20   int mgood1;
  21 } vgood3;
  22
  23 // Functions should never trigger a warning.
  24 void fgood1(void);
  25 void fgood2(void) {
  26   int lgood1;
  27   static int lgood2;
  28 }
  29 static void fgood3(void) {
  30   int lgood3;
  31   static int lgood4;
  32 }
  33
  34 // Structures, namespaces and classes should be unaffected.
  35 struct sgood1 {
  36   int mgood2;
  37 };
  38 struct {
  39   int mgood3;
  40 } sgood2;
  41 class CGood1 {
  42   static int MGood1;
  43 };
  44 int CGood1::MGood1;
  45 namespace {
  46   int mgood4;
  47 }
  48
  49 class C {
  50   void test() {
  51     static int x = 0; // no-warn
  52   }
  53 };
  54
  55 // There is also no need to use static in anonymous namespaces.
  56 namespace {
  57   int vgood4;
  58 }
  59
  60 inline int inline_var = 0;
  61 const int const_var = 0;
  62 constexpr int constexpr_var = 0;
  63 inline constexpr int inline_constexpr_var = 0;
  64 extern const int extern_const_var = 0; // expected-warning {{no previous extern declaration}}
  65 // expected-note@-1{{declare 'static' if the variable is not intended to be used outside of this translation unit}}
  66 extern constexpr int extern_constexpr_var = 0; // expected-warning {{no previous extern declaration}}
  67 // expected-note@-1{{declare 'static' if the variable is not intended to be used outside of this translation unit}}
  68
  69 template<typename> int var_template = 0;
  70 template<typename> constexpr int const_var_template = 0;
  71 template<typename> static int static_var_template = 0;
  72
  73 template<typename T> int var_template<T*>;
  74
  75 template int var_template<int[1]>;
  76 int use_var_template() { return var_template<int[2]>; }
  77 template int var_template<int[3]>;
  78 extern template int var_template<int[4]>;
  79 template<> int var_template<int[5]>; // expected-warning {{no previous extern declaration}}
  80 // expected-note@-1{{declare 'static' if the variable is not intended to be used outside of this translation unit}}
  81
  82 // FIXME: We give this specialization internal linkage rather than inheriting
  83 // the linkage from the template! We should not warn here.
  84 template<> int static_var_template<int[5]>; // expected-warning {{no previous extern declaration}}
  85 // expected-note@-1{{declare 'static' if the variable is not intended to be used outside of this translation unit}}