clang/test/Sema/attr-alwaysinline.cpp

   1 // RUN: %clang_cc1 -verify -fsyntax-only %s -Wno-c++17-extensions
   2
   3 int bar();
   4
   5 [[gnu::always_inline]] void always_inline_fn(void) {}
   6 // expected-note@+1{{conflicting attribute is here}}
   7 [[gnu::flatten]] void flatten_fn(void) {}
   8 // expected-note@+1{{conflicting attribute is here}}
   9 [[gnu::noinline]] void noinline_fn(void) {}
  10
  11 void foo() {
  12   [[clang::always_inline]] bar();
  13   [[clang::always_inline(0)]] bar(); // expected-error {{'always_inline' attribute takes no arguments}}
  14   int x;
  15   [[clang::always_inline]] int i = bar();  // expected-warning {{'always_inline' attribute only applies to functions and statements}}
  16   [[clang::always_inline]] x = 0;          // expected-warning {{'always_inline' attribute is ignored because there exists no call expression inside the statement}}
  17   [[clang::always_inline]] { asm("nop"); } // expected-warning {{'always_inline' attribute is ignored because there exists no call expression inside the statement}}
  18   [[clang::always_inline]] label : x = 1;  // expected-warning {{'always_inline' attribute only applies to functions and statements}}
  19
  20   [[clang::always_inline]] always_inline_fn();
  21   [[clang::always_inline]] noinline_fn(); // expected-warning {{statement attribute 'always_inline' has higher precedence than function attribute 'noinline'}}
  22   [[clang::always_inline]] flatten_fn();  // expected-warning {{statement attribute 'always_inline' has higher precedence than function attribute 'flatten'}}
  23
  24   [[gnu::always_inline]] bar();         // expected-warning {{attribute is ignored on this statement as it only applies to functions; use '[[clang::always_inline]]' on statements}}
  25   __attribute__((always_inline)) bar(); // expected-warning {{attribute is ignored on this statement as it only applies to functions; use '[[clang::always_inline]]' on statements}}
  26 }
  27
  28 [[clang::always_inline]] static int i = bar(); // expected-warning {{'always_inline' attribute only applies to functions and statements}}
  29
  30 // This used to crash the compiler.
  31 template<int D>
  32 int foo(int x) {
  33   [[clang::always_inline]] return foo<D-1>(x + 1);
  34 }
  35
  36 template<int D>
  37 [[gnu::noinline]]
  38 int dependent(int x){ return x + D;} // #DEP
  39 [[gnu::noinline]]
  40 int non_dependent(int x){return x;} // #NO_DEP
  41
  42 template<int D> [[gnu::noinline]]
  43 int baz(int x) { // #BAZ
  44   // expected-warning@+2{{statement attribute 'always_inline' has higher precedence than function attribute 'noinline'}}
  45   // expected-note@#NO_DEP{{conflicting attribute is here}}
  46   [[clang::always_inline]] non_dependent(x);
  47   if constexpr (D>0) {
  48     // expected-warning@+6{{statement attribute 'always_inline' has higher precedence than function attribute 'noinline'}}
  49     // expected-note@#NO_DEP{{conflicting attribute is here}}
  50     // expected-warning@+4 3{{statement attribute 'always_inline' has higher precedence than function attribute 'noinline'}}
  51     // expected-note@#BAZ 3{{conflicting attribute is here}}
  52     // expected-note@#BAZ_INST 3{{in instantiation}}
  53     // expected-note@+1 3{{in instantiation}}
  54     [[clang::always_inline]] return non_dependent(x), baz<D-1>(x + 1);
  55   }
  56   return x;
  57 }
  58
  59 // We can't suppress if there is a variadic involved.
  60 template<int ... D>
  61 int variadic_baz(int x) {
  62   // Diagnoses NO_DEP 2x, once during phase 1, the second during instantiation.
  63   // Dianoses DEP 3x, once per variadic expansion.
  64   // expected-warning@+5 2{{statement attribute 'always_inline' has higher precedence than function attribute 'noinline'}}
  65   // expected-note@#NO_DEP 2{{conflicting attribute is here}}
  66   // expected-warning@+3 3{{statement attribute 'always_inline' has higher precedence than function attribute 'noinline'}}
  67   // expected-note@#DEP 3{{conflicting attribute is here}}
  68   // expected-note@#VARIADIC_INST{{in instantiation}}
  69   [[clang::always_inline]] return non_dependent(x) + (dependent<D>(x) + ...);
  70 }
  71
  72 void use() {
  73   baz<3>(0); // #BAZ_INST
  74   variadic_baz<0, 1, 2>(0); // #VARIADIC_INST
  75
  76 }