Fix bug in computing POD-for-layout.

A class with a field of non-POD-for-layout type is not POD-for-layout.
This computation should not depend on whether the field is of POD type
in the language sense.

Fixes PR16537.

Patch by Josh Magee.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@186741 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/docs/ReleaseNotes.rst b/docs/ReleaseNotes.rst
index d37554799f88e0b5e5583a8b746b9778a1166995..601f56654d8de97e209a41c555ecb529fbba8685 100644 (file)
--- a/docs/ReleaseNotes.rst
+++ b/docs/ReleaseNotes.rst
@@ -74,6 +74,10 @@ C11 Feature Support
 C++ Language Changes in Clang
 -----------------------------
 
+- Fixed an ABI regression, introduced in Clang 3.2, which affected
+  member offsets for classes inheriting from certain classes with tail padding.
+  See PR16537.
+
 - ...
 
 C++11 Feature Support

diff --git a/lib/AST/DeclCXX.cpp b/lib/AST/DeclCXX.cpp
index dacb867df65eb487f331fe0e6871e3f6ed37f48e..ceebbe01cc0a1c9f538c0c5208f9d0a98c614867 100644 (file)
--- a/lib/AST/DeclCXX.cpp
+++ b/lib/AST/DeclCXX.cpp
@@ -662,7 +662,7 @@ void CXXRecordDecl::addedMember(Decl *D) {
       if (!Context.getLangOpts().ObjCAutoRefCount ||
           T.getObjCLifetime() != Qualifiers::OCL_ExplicitNone)
         setHasObjectMember(true);
-    } else if (!T.isPODType(Context))
+    } else if (!T.isCXX98PODType(Context))
       data().PlainOldData = false;
     
     if (T->isReferenceType()) {

diff --git a/test/SemaCXX/class-layout.cpp b/test/SemaCXX/class-layout.cpp
index f2ff9fcfd7c195e6f8f6606e317042bbe1ff39d8..64c8ceba995eb80ed1ac00e292d2b8f358f034fd 100644 (file)
--- a/test/SemaCXX/class-layout.cpp
+++ b/test/SemaCXX/class-layout.cpp
@@ -1,4 +1,5 @@
-// RUN: %clang_cc1 -triple x86_64-unknown-unknown %s -fsyntax-only -verify 
+// RUN: %clang_cc1 -triple x86_64-unknown-unknown %s -fsyntax-only -verify -std=c++98
+// RUN: %clang_cc1 -triple x86_64-unknown-unknown %s -fsyntax-only -verify -std=c++11
 // expected-no-diagnostics
 
 #define SA(n, p) int a##n[(p) ? 1 : -1]
@@ -103,3 +104,469 @@ struct H { G g; };
 SA(0, sizeof(H) == 24);
 
 }
+
+namespace PR16537 {
+namespace test1 {
+  struct pod_in_11_only {
+  private:
+    long long x;
+  };
+   
+  struct tail_padded_pod_in_11_only {
+    pod_in_11_only pod11;
+    char tail_padding;
+  };
+    
+  struct might_use_tail_padding : public tail_padded_pod_in_11_only {
+    char may_go_into_tail_padding;
+  };
+
+  SA(0, sizeof(might_use_tail_padding) == 16);
+}
+
+namespace test2 {
+  struct pod_in_11_only {
+  private:
+    long long x;
+  };
+   
+  struct tail_padded_pod_in_11_only {
+    pod_in_11_only pod11 __attribute__((aligned(16)));
+  };
+    
+  struct might_use_tail_padding : public tail_padded_pod_in_11_only {
+    char may_go_into_tail_padding;
+  };
+
+  SA(0, sizeof(might_use_tail_padding) == 16);
+}
+
+namespace test3 {
+  struct pod_in_11_only {
+  private:
+    long long x;
+  };
+   
+  struct tail_padded_pod_in_11_only {
+    pod_in_11_only pod11;
+    char tail_padding;
+  };
+
+  struct second_base {
+      char foo;
+  };
+    
+  struct might_use_tail_padding : public tail_padded_pod_in_11_only, public second_base {
+
+  };
+  SA(0, sizeof(might_use_tail_padding) == 16);
+}
+
+namespace test4 {
+  struct pod_in_11_only {
+  private:
+    long long x;
+  };
+   
+  struct tail_padded_pod_in_11_only {
+    pod_in_11_only pod11;
+    char tail_padding;
+  };
+
+  struct second_base {
+    char foo;
+  };
+    
+  struct might_use_tail_padding : public tail_padded_pod_in_11_only, public second_base {
+    char may_go_into_tail_padding;
+  };
+  SA(0, sizeof(might_use_tail_padding) == 16);
+}
+
+namespace test5 {
+  struct pod_in_11_only {
+  private:
+    long long x;
+  };
+
+  struct pod_in_11_only2 {
+  private:
+    long long x;
+  };
+   
+  struct tail_padded_pod_in_11_only {
+    pod_in_11_only pod11;
+    char tail_padding;
+  };
+
+  struct second_base {
+    pod_in_11_only2 two;
+    char foo;
+  };
+    
+  struct might_use_tail_padding : public tail_padded_pod_in_11_only, public second_base {
+    char may_go_into_tail_padding;
+  };
+  SA(0, sizeof(might_use_tail_padding) == 32);
+}
+
+namespace test6 {
+  struct pod_in_11_only {
+  private:
+    long long x;
+  };
+
+  struct pod_in_11_only2 {
+  private:
+    long long x;
+  };
+   
+  struct tail_padded_pod_in_11_only {
+    pod_in_11_only pod11;
+    char tail_padding;
+  };
+
+  struct second_base {
+    pod_in_11_only2 two;
+    char foo;
+  };
+    
+  struct might_use_tail_padding : public tail_padded_pod_in_11_only, public second_base {
+    char may_go_into_tail_padding;
+  };
+  SA(0, sizeof(might_use_tail_padding) == 32);
+}
+
+namespace test7 {
+  struct pod_in_11_only {
+  private:
+    long long x;
+  };
+   
+  struct tail_padded_pod_in_11_only {
+    pod_in_11_only pod11;
+    pod_in_11_only pod12;
+    char tail_padding;
+  };
+    
+  struct might_use_tail_padding : public tail_padded_pod_in_11_only {
+    char may_go_into_tail_padding;
+  };
+
+  SA(0, sizeof(might_use_tail_padding) == 24);
+}
+
+namespace test8 {
+  struct pod_in_11_only {
+  private:
+    long long x;
+  };
+   
+  struct tail_padded_pod_in_11_only {
+    pod_in_11_only pod11;
+    char tail_padding;
+  };
+
+  struct another_layer {
+    tail_padded_pod_in_11_only pod;
+    char padding;
+  };
+    
+  struct might_use_tail_padding : public another_layer {
+    char may_go_into_tail_padding;
+  };
+
+  SA(0, sizeof(might_use_tail_padding) == 24);
+}
+
+namespace test9 {
+  struct pod_in_11_only {
+  private:
+    long long x;
+  };
+   
+  struct tail_padded_pod_in_11_only {
+    pod_in_11_only pod11;
+    char tail_padding;
+  };
+
+  struct another_layer : tail_padded_pod_in_11_only {
+  };
+    
+  struct might_use_tail_padding : public another_layer {
+    char may_go_into_tail_padding;
+  };
+
+  SA(0, sizeof(might_use_tail_padding) == 16);
+}
+
+namespace test10 {
+  struct pod_in_11_only {
+  private:
+    long long x;
+  };
+   
+  struct A {
+    pod_in_11_only a;
+    char apad;
+  };
+
+  struct B {
+    char b;
+  };
+
+  struct C {
+    pod_in_11_only c;
+    char cpad;
+  };
+
+  struct D {
+    char d;
+  };
+    
+  struct might_use_tail_padding : public A, public B, public C, public D {
+  };
+
+  SA(0, sizeof(might_use_tail_padding) == 32);
+}
+
+namespace test11 {
+  struct pod_in_11_only {
+  private:
+    long long x;
+  };
+   
+  struct A {
+    pod_in_11_only a;
+    char apad;
+  };
+
+  struct B {
+    char b_pre;
+    pod_in_11_only b;
+    char bpad;
+  };
+
+  struct C {
+    char c_pre;
+    pod_in_11_only c;
+    char cpad;
+  };
+
+  struct D {
+    char d_pre;
+    pod_in_11_only d;
+    char dpad;
+  };
+    
+  struct might_use_tail_padding : public A, public B, public C, public D {
+    char m;
+  };
+
+  SA(0, sizeof(might_use_tail_padding) == 88);
+}
+
+namespace test12 {
+  struct pod_in_11_only {
+  private:
+    long long x;
+  };
+   
+  struct A {
+    pod_in_11_only a __attribute__((aligned(128)));
+  };
+
+  struct B {
+    char bpad;
+  };
+
+  struct C {
+    char cpad;
+  };
+
+  struct D {
+    char dpad;
+  };
+    
+  struct might_use_tail_padding : public A, public B, public C, public D {
+    char m;
+  };
+  SA(0, sizeof(might_use_tail_padding) == 128);
+}
+
+namespace test13 {
+  struct pod_in_11_only {
+  private:
+    long long x;
+  };
+   
+  struct A {
+    pod_in_11_only a;
+    char apad;
+  };
+
+  struct B {
+  };
+
+  struct C {
+    char c_pre;
+    pod_in_11_only c;
+    char cpad;
+  };
+
+  struct D {
+  };
+    
+  struct might_use_tail_padding : public A, public B, public C, public D {
+    char m;
+  };
+  SA(0, sizeof(might_use_tail_padding) == 40);
+}
+
+namespace test14 {
+  struct pod_in_11_only {
+  private:
+    long long x;
+  };
+   
+  struct A {
+    pod_in_11_only a;
+    char apad;
+  };
+
+  struct might_use_tail_padding : public A {
+    struct {
+      int : 0;
+    } x;
+  };
+  SA(0, sizeof(might_use_tail_padding) == 16);
+}
+
+namespace test15 {
+  struct pod_in_11_only {
+  private:
+    long long x;
+  };
+   
+  struct A {
+    pod_in_11_only a;
+    char apad;
+  };
+
+  struct might_use_tail_padding : public A {
+    struct {
+      char a:1;
+      char b:2;
+      char c:2;
+      char d:2;
+      char e:1;
+    } x;
+  };
+  SA(0, sizeof(might_use_tail_padding) == 16);
+}
+
+namespace test16 {
+  struct pod_in_11_only {
+  private:
+    long long x;
+  };
+   
+  struct A  {
+    pod_in_11_only a;
+    char apad;
+  };
+
+  struct B {
+    char bpod;
+    pod_in_11_only b;
+    char bpad;
+  };
+
+  struct C : public A, public B {
+  };
+  
+  struct D : public C {
+  };
+
+  struct might_use_tail_padding : public D {
+    char m;
+  };
+  SA(0, sizeof(might_use_tail_padding) == 40);
+}
+
+namespace test17 {
+  struct pod_in_11_only {
+  private:
+    long long x;
+  };
+   
+  struct A {
+    pod_in_11_only a __attribute__((aligned(512)));
+  };
+
+  struct B {
+    char bpad;
+    pod_in_11_only foo;
+    char btail;
+  };
+
+  struct C {
+    char cpad;
+  };
+
+  struct D {
+    char dpad;
+  };
+    
+  struct might_use_tail_padding : public A, public B, public C, public D {
+    char a;
+  };
+  SA(0, sizeof(might_use_tail_padding) == 512);
+}
+
+namespace test18 {
+  struct pod_in_11_only {
+  private:
+    long long x;
+  };
+   
+  struct A  {
+    pod_in_11_only a;
+    char apad;
+  };
+
+  struct B {
+    char bpod;
+    pod_in_11_only b;
+    char bpad;
+  };
+
+  struct A1  {
+    pod_in_11_only a;
+    char apad;
+  };
+
+  struct B1 {
+    char bpod;
+    pod_in_11_only b;
+    char bpad;
+  };
+
+  struct C : public A, public B {
+  };
+
+  struct D : public A1, public B1 {
+  };
+
+  struct E : public D, public C {
+  };
+
+  struct F : public E {
+  };
+
+  struct might_use_tail_padding : public F {
+    char m;
+  };
+  SA(0, sizeof(might_use_tail_padding) == 80);
+}
+} // namespace PR16537