Recognition of empty structures and unions is moved to semantic stage

Differential Revision: http://llvm-reviews.chandlerc.com/D586

llvm-svn: 183609

4 files changed, 72 insertions, 2 deletions

diff --git a/clang/test/Parser/declarators.c b/clang/test/Parser/declarators.c
index f63b59f7caa..210a8e2befc 100644
--- a/clang/test/Parser/declarators.c
+++ b/clang/test/Parser/declarators.c
@@ -108,7 +108,8 @@ void test18() {
 }
 
 enum E1 { e1 }: // expected-error {{expected ';'}}
-struct EnumBitfield {
+struct EnumBitfield { // expected-warning {{struct without named members is a GNU extension}}
   enum E2 { e2 } : 4; // ok
   struct S { int n; }: // expected-error {{expected ';'}}
+
 };
diff --git a/clang/test/Sema/array-init.c b/clang/test/Sema/array-init.c
index f92852f341b..ae2c7425662 100644
--- a/clang/test/Sema/array-init.c
+++ b/clang/test/Sema/array-init.c
@@ -226,7 +226,8 @@ void emptyInit() {struct {} x[] = {6};} //expected-warning{{empty struct is a GN
 // expected-error{{initializer for aggregate with no elements}}
 
 void noNamedInit() {
-  struct {int:5;} x[] = {6}; //expected-error{{initializer for aggregate with no elements}}
+  struct {int:5;} x[] = {6}; //expected-error{{initializer for aggregate with no elements}} \
+// expected-warning {{struct without named members is a GNU extension}}
 }
 struct {int a; int:5;} noNamedImplicit[] = {1,2,3};
 int noNamedImplicitCheck[sizeof(noNamedImplicit) == 3 * sizeof(*noNamedImplicit) ? 1 : -1];
diff --git a/clang/test/Sema/empty1.c b/clang/test/Sema/empty1.c
new file mode 100644
index 00000000000..cd4aca8e473
--- /dev/null
+++ b/clang/test/Sema/empty1.c
@@ -0,0 +1,25 @@
+// RUN: %clang_cc1 %s -fsyntax-only -verify -Wc++-compat
+
+struct emp_1 { // expected-warning {{empty struct has size 0 in C, size 1 in C++}}
+};
+
+union emp_2 { // expected-warning {{empty union has size 0 in C, size 1 in C++}}
+};
+
+struct emp_3 { // expected-warning {{struct with only bit-fields of width 0 has size 0 in C, size 1 in C++}}
+  int : 0;
+};
+
+union emp_4 { // expected-warning {{union with only bit-fields of width 0 has size 0 in C, size 1 in C++}}
+  int : 0;
+};
+
+struct emp_5 { // expected-warning {{struct with only bit-fields of width 0 has size 0 in C, size 1 in C++}}
+  int : 0;
+  int : 0;
+};
+
+union emp_6 { // expected-warning {{union with only bit-fields of width 0 has size 0 in C, size 1 in C++}}
+  int : 0;
+  int : 0;
+};
diff --git a/clang/test/Sema/empty2.c b/clang/test/Sema/empty2.c
new file mode 100644
index 00000000000..68da5a8ee8a
--- /dev/null
+++ b/clang/test/Sema/empty2.c
@@ -0,0 +1,43 @@
+// RUN: %clang_cc1 %s -fsyntax-only -verify -pedantic
+
+struct emp_1 { // expected-warning {{empty struct is a GNU extension}}
+};
+
+union emp_2 { // expected-warning {{empty union is a GNU extension}}
+};
+
+struct emp_3 { // expected-warning {{struct without named members is a GNU extension}}
+  int : 0;
+};
+
+union emp_4 { // expected-warning {{union without named members is a GNU extension}}
+  int : 0;
+};
+
+struct emp_5 { // expected-warning {{struct without named members is a GNU extension}}
+  int : 0;
+  int : 0;
+};
+
+union emp_6 { // expected-warning {{union without named members is a GNU extension}}
+  int : 0;
+  int : 0;
+};
+
+struct nonamed_1 { // expected-warning {{struct without named members is a GNU extension}}
+  int : 4;
+};
+
+union nonamed_2 { // expected-warning {{union without named members is a GNU extension}}
+  int : 4;
+};
+
+struct nonamed_3 { // expected-warning {{struct without named members is a GNU extension}}
+  int : 4;
+  unsigned int : 4;
+};
+
+union nonamed_4 { // expected-warning {{union without named members is a GNU extension}}
+  int : 4;
+  unsigned int : 4;
+};