clang/test/SemaCXX/c99.cpp

   1 // RUN: %clang_cc1 -fsyntax-only -pedantic -verify=expected,cxx17 -std=c++17 %s
   2 // RUN: %clang_cc1 -fsyntax-only -pedantic -verify=expected,cxx20 -std=c++2a %s
   3
   4 // cxx17-warning@* 0+{{designated initializers are a C++20 extension}}
   5
   6 void f1(int i[static 5]) { // expected-error{{C99}}
   7 }
   8
   9 struct Point { int x; int y; int z[]; }; // expected-warning{{flexible array members are a C99 feature}}
  10
  11 Point p1 = { .x = 17,
  12              y: 25 }; // expected-warning{{use of GNU old-style field designator extension}}
  13
  14 Point p2 = {
  15   .x = 17, // expected-warning {{mixture of designated and non-designated initializers in the same initializer list is a C99 extension}}
  16   25 // expected-note {{first non-designated initializer}}
  17 };
  18
  19 Point p3 = {
  20   .x = 17, // expected-note {{previous initialization is here}}
  21   .x = 18, // expected-warning {{initializer overrides prior initialization of this subobject}}
  22 };
  23
  24 Point p4 = {
  25   .x = 17, // expected-warning {{mixture of designated and non-designated initializers in the same initializer list is a C99 extension}}
  26   25, // expected-note {{first non-designated initializer}}
  27   // expected-note@-1 {{previous initialization is here}}
  28   .y = 18, // expected-warning {{initializer overrides prior initialization of this subobject}}
  29 };
  30
  31 int arr[1] = {[0] = 0}; // expected-warning {{array designators are a C99 extension}}
  32
  33 struct Pt { int x, y; };
  34 struct Rect { Pt tl, br; };
  35 Rect r = {
  36   .tl.x = 0 // expected-warning {{nested designators are a C99 extension}}
  37 };
  38
  39 struct NonTrivial {
  40   NonTrivial();
  41   ~NonTrivial();
  42 };
  43 struct S {
  44   int a;
  45   NonTrivial b;
  46 };
  47 struct T {
  48   S s;
  49 };
  50 S f();
  51
  52 T t1 = {
  53   .s = f()
  54 };
  55
  56 // It's important that we reject this; we would not destroy the existing
  57 // 'NonTrivial' object before overwriting it (and even calling its destructor
  58 // would not necessarily be correct).
  59 T t2 = {
  60   .s = f(), // expected-note {{previous}}
  61   .s.b = NonTrivial() // expected-error {{initializer would partially override prior initialization of object of type 'S' with non-trivial destruction}}
  62   // expected-warning@-1 {{nested}}
  63 };
  64
  65 // FIXME: It might be reasonable to accept this.
  66 T t3 = {
  67   .s = f(), // expected-note {{previous}}
  68   .s.a = 0 // expected-error {{initializer would partially override prior initialization of object of type 'S' with non-trivial destruction}}
  69   // expected-warning@-1 {{nested}}
  70 };