================
@@ -1,45 +1,124 @@
-// RUN: %clang_cc1 -verify -std=c2y -Wall -pedantic -Wno-unused %s
+// RUN: %clang_cc1 -verify=expected,c2y -std=c2y -Wall -pedantic -Wno-unused %s
+// RUN: %clang_cc1 -verify=expected,c89-23 -std=c23 -Wall -pedantic
-Wno-unused %s
+// RUN: %clang_cc1 -verify=expected,c89-23 -std=c17 -Wall -pedantic
-Wno-unused %s
+// RUN: %clang_cc1 -verify=expected,c89-23 -std=c11 -Wall -pedantic
-Wno-unused %s
+// RUN: %clang_cc1 -verify=expected,c89-23 -std=c99 -Wall -pedantic
-Wno-unused %s
+// RUN: %clang_cc1 -verify=expected,c89-23 -std=c89 -Wall -pedantic
-Wno-unused -Wno-comment %s
-/* WG14 N3410: No
+/* WG14 N3410: Clang 24
* Slay Some Earthly Demons XI
*
* It is now ill-formed for the same identifier within a TU to have both
* internal and external linkage.
*/
-void func1() {
- extern int a; // #a
+void func1(void) {
+ extern int a; /* #a */
}
-// This 'a' is the same as the one declared extern above.
-static int a; /* expected-error {{static declaration of 'a' follows non-static
declaration}}
+/* This 'a' is the same as the one declared extern above. */
+static int a; /* c2y-error {{static declaration of 'a' follows non-static
declaration}}
+ c89-23-error {{static declaration of 'a' follows non-static
declaration; behavior is undefined}}
expected-note@#a {{previous declaration is here}}
*/
static int b;
-void func2() {
- // This 'b' is the same as the one declaraed static above, but this is not
- // ill-formed because of C2y 6.2.2p4, which gives this variable internal
- // linkage because the previous declaration had internal linkage.
- extern int b; // Ok
+void func2(void) {
+ /* This 'b' is well-formed, because C2y 6.2.2p6 makes it "inherit" the
+ static linkage of `static int b` above, because the latter is visible.
+ */
+ extern int b; /* Ok */
}
-static int c, d;
-void func3() {
- int c; // no linkage, different object from the one declared above.
- for (int d;;) {
- // This 'c' is the same as the one declared at file scope, but because of
- // the local scope 'c', the file scope 'c' is not visible.
- // FIXME: This should be diagnosed under N3410.
- extern int c;
- // This 'd' is the same as the one declared at file scope as well, but
- // because of the 'd' declared within the for loop, the file scope 'd' is
- // also not visible, same as with 'c'.
- // FIXME: This should be diagnosed under N3410.
- extern int d;
+static int c, d; /* expected-note 2 {{previous definition is here}} */
+void func3(void) {
+ int c; /* no linkage, different object from the one declared above. */
+ {
+ int d; /* no linkage, different object from the file-scope 'd'. */
+ {
+ /* This 'c' is the same as the one declared at file scope, but because
+ of the local scope 'c', the file scope 'c' is not visible. */
+ extern int c; /* c2y-error {{variable 'c' cannot be declared with
external linkage following a declaration with internal linkage}}
+ c89-23-error {{variable 'c' declared with external
linkage following a declaration with internal linkage; behavior is undefined}}
+ */
+ /* This 'd' is the same as the one declared at file scope as well, but
+ because of the enclosing block-scope 'd', the file scope 'd' is also
+ not visible, same as with 'c'. */
+ extern int d; /* c2y-error {{variable 'd' cannot be declared with
external linkage following a declaration with internal linkage}}
+ c89-23-error {{variable 'd' declared with external
linkage following a declaration with internal linkage; behavior is undefined}}
+ */
+ }
}
- for (static int e;;) {
- extern int e; // Ok for the same reason as 'b' above.
+ {
+ static int e;
+ {
+ extern int e; /* Ok for the same reason as 'b' above. */
+ }
}
}
+/* A function parameter shadows the file-scope 'p' the same way a local
+ variable does, so the block-scope 'extern' does not inherit internal
+ linkage and conflicts. */
+static int p; /* expected-note {{previous definition is here}} */
+void func4(int p) {
+ {
+ extern int p; /* c2y-error {{variable 'p' cannot be declared with external
linkage following a declaration with internal linkage}}
+ c89-23-error {{variable 'p' declared with external
linkage following a declaration with internal linkage; behavior is undefined}}
+ */
+ }
+}
+
+static int q;
+void func5(void) {
+ /* No shadow intervenes here, so this 'q' inherits the internal linkage of
+ the file-scope 'q', which is fine. */
+ extern int q; /* #q */
+ {
+ int q; /* no linkage; shadows the declarations above. */
+ {
+ /* The file-scope 'q' is now hidden, so this 'extern' has external
+ linkage and conflicts with the internal-linkage declaration above. */
+ extern int q; /* c2y-error {{variable 'q' cannot be declared with
external linkage following a declaration with internal linkage}}
+ c89-23-error {{variable 'q' declared with external
linkage following a declaration with internal linkage; behavior is undefined}}
+ expected-note@#q {{previous declaration is here}}
+ */
+ }
+ }
+}
+
+void func6(void) {
+ /* No file-scope declaration of 'r' exists, so the block-scope 'extern' just
+ has external linkage and there is no conflict. */
+ {
+ int r; /* no linkage. */
+ {
+ extern int r; /* Ok */
+ }
+ }
+}
+
+static int s; /* expected-note {{previous definition is here}} */
----------------
Endilll wrote:
The diagnostic this note is attached to talks about declarations and not
definitions, so I think this note should read "previous declaration is here".
Consider enabling `-verify-directives` for this test that will force you to put
notes next to their respective diagnostics.
https://github.com/llvm/llvm-project/pull/193567
_______________________________________________
cfe-commits mailing list
[email protected]
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
