forked from OSchip/llvm-project
				
			
		
			
				
	
	
		
			88 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			88 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
| // RUN: %clang_cc1 %s -triple %itanium_abi_triple -fsyntax-only -verify -Wc++-compat
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| 
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| // Note: Empty C structs are 4 bytes in the Microsoft ABI.
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| 
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| struct emp_1 { // expected-warning {{empty struct has size 0 in C, size 1 in C++}}
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| };
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| 
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| union emp_2 { // expected-warning {{empty union has size 0 in C, size 1 in C++}}
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| };
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| 
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| struct emp_3 { // expected-warning {{struct has size 0 in C, size 1 in C++}}
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|   int : 0;
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| };
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| 
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| union emp_4 { // expected-warning {{union has size 0 in C, size 1 in C++}}
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|   int : 0;
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| };
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| 
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| struct emp_5 { // expected-warning {{struct has size 0 in C, size 1 in C++}}
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|   int : 0;
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|   int : 0;
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| };
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| 
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| union emp_6 { // expected-warning {{union has size 0 in C, size 1 in C++}}
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|   int : 0;
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|   int : 0;
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| };
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| 
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| struct emp_7 { // expected-warning {{struct has size 0 in C, size 1 in C++}}
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|   struct emp_1 f1;
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| };
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| 
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| union emp_8 { // expected-warning {{union has size 0 in C, size 1 in C++}}
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|   struct emp_1 f1;
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| };
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| 
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| struct emp_9 { // expected-warning {{struct has size 0 in C, non-zero size in C++}}
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|   struct emp_1 f1;
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|   union emp_2 f2;
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| };
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| 
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| // Checks for pointer subtraction (PR15683)
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| struct emp_1 *func_1p(struct emp_1 *x) { return x - 5; }
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| 
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| int func_1() {
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|   struct emp_1 v[1];
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|   return v - v; // expected-warning {{subtraction of pointers to type 'struct emp_1' of zero size has undefined behavior}}
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| }
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| 
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| int func_2(struct emp_1 *x) {
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|   return 1 + x - x; // expected-warning {{subtraction of pointers to type 'struct emp_1' of zero size has undefined behavior}}
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| }
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| 
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| int func_3(struct emp_1 *x, struct emp_1 *y) {
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|   return x - y; // expected-warning {{subtraction of pointers to type 'struct emp_1' of zero size has undefined behavior}}
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| }
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| 
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| int func_4(struct emp_1 *x, const struct emp_1 *y) {
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|   return x - y; // expected-warning {{subtraction of pointers to type 'struct emp_1' of zero size has undefined behavior}}
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| }
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| 
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| int func_5(volatile struct emp_1 *x, const struct emp_1 *y) {
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|   return x - y; // expected-warning {{subtraction of pointers to type 'struct emp_1' of zero size has undefined behavior}}
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| }
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| 
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| int func_6() {
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|   union emp_2 v[1];
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|   return v - v; // expected-warning {{subtraction of pointers to type 'union emp_2' of zero size has undefined behavior}}
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| }
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| 
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| struct A; // expected-note {{forward declaration of 'struct A'}}
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| 
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| int func_7(struct A *x, struct A *y) {
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|   return x - y; // expected-error {{arithmetic on a pointer to an incomplete type 'struct A'}}
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| }
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| 
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| int func_8(struct emp_1 (*x)[10], struct emp_1 (*y)[10]) {
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|   return x - y; // expected-warning {{subtraction of pointers to type 'struct emp_1 [10]' of zero size has undefined behavior}}
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| }
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| 
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| int func_9(struct emp_1 (*x)[], struct emp_1 (*y)[]) {
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|   return x - y; // expected-error {{arithmetic on a pointer to an incomplete type 'struct emp_1 []'}}
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| }
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| 
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| int func_10(int (*x)[0], int (*y)[0]) {
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|   return x - y; // expected-warning {{subtraction of pointers to type 'int [0]' of zero size has undefined behavior}}
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| }
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