When we parse a tag specifier, keep track of whether that tag
specifier resulted in the creation of a new TagDecl node, which
happens either when the tag specifier was a definition or when the tag
specifier was the first declaration of that tag type. This information
has several uses, the first of which is implemented in this commit:
1) In C++, one is not allowed to define tag types within a type
specifier (e.g., static_cast<struct S { int x; } *>(0) is
ill-formed) or within the result or parameter types of a
function. We now diagnose this.
2) We can extend DeclGroups to contain information about any tags
that are declared/defined within the declaration specifiers of a
variable, e.g.,
struct Point { int x, y, z; } p;
This will help improve AST printing and template instantiation,
among other things.
3) For C99, we can keep track of whether a tag type is defined
within the type of a parameter, to properly cope with cases like,
e.g.,
int bar(struct T2 { int x; } y) {
struct T2 z;
}
We can also do similar things wherever there is a type specifier,
e.g., to keep track of where the definition of S occurs in this
legal C99 code:
(struct S { int x, y; } *)0
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@72555 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/SemaCXX/type-definition-in-specifier.cpp b/test/SemaCXX/type-definition-in-specifier.cpp
new file mode 100644
index 0000000..60c28b0
--- /dev/null
+++ b/test/SemaCXX/type-definition-in-specifier.cpp
@@ -0,0 +1,25 @@
+// RUN: clang-cc -fsyntax-only -verify %s
+
+struct S0;
+struct S1;
+struct S2;
+struct S3;
+struct S4;
+struct S5;
+struct S6;
+
+struct S0 { int x; };
+
+void f0() {
+ typedef struct S1 { int x; } S1_typedef;
+
+ (void)((struct S2 { int x; }*)0); // expected-error{{can not be defined}}
+
+ struct S3 { int x; } s3;
+
+ (void)static_cast<struct S4 { int x; } *>(0); // expected-error{{can not be defined}}
+}
+
+struct S5 { int x; } f1() { return S5(); } // expected-error{{result type}}
+
+void f2(struct S6 { int x; } p); // expected-error{{parameter type}}