Cope with anonymous tags defined within declarators by structurally

comparing their types under the assumption that they are equivalent,
rather than importing the types and then checking for compatibility. A
few minor tweaks here:
  - Teach structural matching to handle compatibility between
  function types with prototypes and those without prototypes.
  - Teach structural matching that an incomplete record decl is the
  same as any other record decl with the same name.
  - Keep track of pairs of declarations that we have already checked
  (but failed to find as structurally matching), so we don't emit
  diagnostics repeatedly.
  - When importing a typedef of an anonymous tag, be sure to link the
  imported tag type to its typedef.

With these changes, we survive a repeated import of <stdlib.h> and
<stdio.h>. Alas, the ASTNodeImporter is getting a little grotty.

llvm-svn: 96298

1 files changed, 3 insertions, 0 deletions

diff --git a/clang/test/ASTMerge/struct.c b/clang/test/ASTMerge/struct.c
index d71436f2fcf..e72b93b249f 100644
--- a/clang/test/ASTMerge/struct.c
+++ b/clang/test/ASTMerge/struct.c
@@ -34,6 +34,9 @@
 // CHECK: struct1.c:56:10: warning: type 'struct DeeperError' has incompatible definitions in different translation units
 // CHECK: struct1.c:56:35: note: field 'f' has type 'int' here
 // CHECK: struct2.c:53:37: note: field 'f' has type 'float' here
+// CHECK: struct1.c:54:8: warning: type 'struct DeepError' has incompatible definitions in different translation units
+// CHECK: struct1.c:56:41: note: field 'Deeper' has type 'struct DeeperError *' here
+// CHECK: struct2.c:53:43: note: field 'Deeper' has type 'struct DeeperError *' here
 // CHECK: struct2.c:54:3: error: external variable 'xDeep' declared with incompatible types in different translation units ('struct DeepError' vs. 'struct DeepError')
 // CHECK: struct1.c:57:3: note: declared here with type 'struct DeepError'
 // CHECK: 37 diagnostics