[ODRHash] Do not rely on Type* when computing the hash.

ODRHash aims to provide Cross-TU stable hashing. Making clang::Type pointer
part of the hash connects (remotely) the ODRHash with the TU-specific
::Profile hasher.

r332281 exposed the issue by changing the way the ASTContext different
elaborated types if there is an owning tag. In that case, ODRHash stores two
 different types in its TypeMap which yields false ODR violation in modules.

The current state of implementation shouldn't need the TypeMap concept
anymore. Rip it out.

Differential Revision: https://reviews.llvm.org/D48524

llvm-svn: 335853

diff --git a/clang/include/clang/AST/ODRHash.h b/clang/include/clang/AST/ODRHash.h
index c9e8027..d4cddb8 100644 (file)
--- a/clang/include/clang/AST/ODRHash.h
+++ b/clang/include/clang/AST/ODRHash.h
@@ -40,7 +40,6 @@ class ODRHash {
   // Use DenseMaps to convert from DeclarationName and Type pointers
   // to an index value.
   llvm::DenseMap<DeclarationName, unsigned> DeclNameMap;
-  llvm::DenseMap<const Type*, unsigned> TypeMap;
 
   // Save space by processing bools at the end.
   llvm::SmallVector<bool, 128> Bools;

diff --git a/clang/lib/AST/ODRHash.cpp b/clang/lib/AST/ODRHash.cpp
index 126b6de..ef1235e 100644 (file)
--- a/clang/lib/AST/ODRHash.cpp
+++ b/clang/lib/AST/ODRHash.cpp
@@ -180,7 +180,6 @@ void ODRHash::AddTemplateParameterList(const TemplateParameterList *TPL) {
 
 void ODRHash::clear() {
   DeclNameMap.clear();
-  TypeMap.clear();
   Bools.clear();
   ID.clear();
 }
@@ -770,14 +769,6 @@ public:
 
 void ODRHash::AddType(const Type *T) {
   assert(T && "Expecting non-null pointer.");
-  auto Result = TypeMap.insert(std::make_pair(T, TypeMap.size()));
-  ID.AddInteger(Result.first->second);
-  // On first encounter of a Type pointer, process it.  Every time afterwards,
-  // only the index value is needed.
-  if (!Result.second) {
-    return;
-  }
-
   ODRTypeVisitor(ID, *this).Visit(T);
 }
 

diff --git a/clang/test/Modules/Inputs/odr_hash-elaborated-types/first.h b/clang/test/Modules/Inputs/odr_hash-elaborated-types/first.h
new file mode 100644 (file)
index 0000000..d2c4a03
--- /dev/null
+++ b/clang/test/Modules/Inputs/odr_hash-elaborated-types/first.h
@@ -0,0 +1,6 @@
+#ifndef FIRST
+#define FIRST
+
+#include "textual_time.h"
+
+#endif

diff --git a/clang/test/Modules/Inputs/odr_hash-elaborated-types/module.modulemap b/clang/test/Modules/Inputs/odr_hash-elaborated-types/module.modulemap
new file mode 100644 (file)
index 0000000..94cb4c1
--- /dev/null
+++ b/clang/test/Modules/Inputs/odr_hash-elaborated-types/module.modulemap
@@ -0,0 +1,5 @@
+module M {
+  module first { header "first.h" export *}
+  module second { header "second.h" export *}
+  export *
+}

diff --git a/clang/test/Modules/Inputs/odr_hash-elaborated-types/second.h b/clang/test/Modules/Inputs/odr_hash-elaborated-types/second.h
new file mode 100644 (file)
index 0000000..577cf11
--- /dev/null
+++ b/clang/test/Modules/Inputs/odr_hash-elaborated-types/second.h
@@ -0,0 +1,6 @@
+#ifndef SECOND
+#define SECOND
+
+#include "textual_stat.h"
+
+#endif

diff --git a/clang/test/Modules/Inputs/odr_hash-elaborated-types/textual_stat.h b/clang/test/Modules/Inputs/odr_hash-elaborated-types/textual_stat.h
new file mode 100644 (file)
index 0000000..5dad510
--- /dev/null
+++ b/clang/test/Modules/Inputs/odr_hash-elaborated-types/textual_stat.h
@@ -0,0 +1,11 @@
+#ifndef _SYS_STAT_H
+#define _SYS_STAT_H
+
+#include "textual_time.h"
+
+struct stat {
+  struct timespec st_atim;
+  struct timespec st_mtim;
+};
+
+#endif

diff --git a/clang/test/Modules/Inputs/odr_hash-elaborated-types/textual_time.h b/clang/test/Modules/Inputs/odr_hash-elaborated-types/textual_time.h
new file mode 100644 (file)
index 0000000..2a2a89c
--- /dev/null
+++ b/clang/test/Modules/Inputs/odr_hash-elaborated-types/textual_time.h
@@ -0,0 +1,6 @@
+#ifndef _TIME_H
+#define _TIME_H
+
+struct timespec { };
+
+#endif

diff --git a/clang/test/Modules/odr_hash-elaborated-types.cpp b/clang/test/Modules/odr_hash-elaborated-types.cpp
new file mode 100644 (file)
index 0000000..7dd11ac
--- /dev/null
+++ b/clang/test/Modules/odr_hash-elaborated-types.cpp
@@ -0,0 +1,12 @@
+// RUN: rm -rf %t
+// RUN: %clang_cc1 -std=c++1z -I%S/Inputs/odr_hash-elaborated-types -verify %s
+// RUN: %clang_cc1 -std=c++1z -fmodules -fmodules-local-submodule-visibility -fmodule-map-file=%S/Inputs/odr_hash-elaborated-types/module.modulemap -fmodules-cache-path=%t -x c++ -I%S/Inputs/odr_hash-elaborated-types -verify %s
+
+#include "textual_stat.h"
+
+#include "first.h"
+#include "second.h"
+
+void use() { struct stat value; }
+
+// expected-no-diagnostics