[Attr] Don't print implicit attributes

[jdenny]

Summary

Fixes bug reported at:

http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20180514/228390.html

[aaron.ballman]

LGTM!

lib/AST/DeclPrinter.cpp

 
 void DeclPrinter::prettyPrintAttributes(Decl *D) {
   if (Policy.PolishForDeclaration)
     return;
 
   if (D->hasAttrs()) {
     AttrVec &Attrs = D->getAttrs();
     for (auto *A : Attrs) {
-      if (A->isInherited())
+      if (A->isInherited() || A->isImplicit())
         continue;
       switch (A->getKind()) {
 #define ATTR(X)
 #define PRAGMA_SPELLING_ATTR(X) case attr::X:
 #include "clang/Basic/AttrList.inc"
         break;
       default:
         A->printPretty(Out, Policy);

test/Misc/ast-print-record-decl.c

 // Repeat for C++ (BASES helps ensure we're printing as C++ not as C):
 //
 //   First check compiling and printing of this file.
 //
 //   RUN: %clang -target x86_64-linux -Xclang -verify -S -emit-llvm \
 //   RUN:        -DKW=struct -DBASES=' : B' -o - -xc++ %s \
 //   RUN: | FileCheck --check-prefixes=CHECK,LLVM %s
 //
-//   RUN: %clang_cc1 -verify -triple x86_64-linux -ast-print -DKW=struct -DBASES=' : B' -xc++ %s \
-//   RUN: > %t.cpp
+//   RUN: %clang_cc1 -verify -ast-print -DKW=struct -DBASES=' : B' -xc++ %s \
+//   RUN:            > %t.cpp
 //   RUN: FileCheck --check-prefixes=CHECK,PRINT,PRINT-CXX -DKW=struct \
 //   RUN:           -DBASES=' : B' %s --input-file %t.cpp
 //
 //   Now check compiling and printing of the printed file.
 //
-//   RUN: echo "// expected""-warning@* 10 {{'T' is deprecated}}" >> %t.cpp
-//   RUN: echo "// expected""-note@* 10 {{'T' has been explicitly marked deprecated here}}" >> %t.cpp
+//   RUN: echo "// expected""-warning@* 10 {{'T' is deprecated}}" > %t.diags
+//   RUN: echo "// expected""-note@* 10 {{'T' has been explicitly marked deprecated here}}" >> %t.diags
+//   RUN: cat %t.diags >> %t.cpp
 //
 //   RUN: %clang -target x86_64-linux -Xclang -verify -S -emit-llvm -o - %t.cpp \
 //   RUN: | FileCheck --check-prefixes=CHECK,LLVM %s
 //
-//   RUN: %clang_cc1 -verify -triple x86_64-linux -ast-print %t.cpp \
+//   RUN: %clang_cc1 -verify -ast-print %t.cpp \
+//   RUN: | FileCheck --check-prefixes=CHECK,PRINT,PRINT-CXX -DKW=struct \
+//   RUN:             -DBASES=' : B' %s
+//
+//   Make sure implicit attributes aren't printed.  See comments in inMemberPtr
+//   for details.
+//
+//   RUN: %clang_cc1 -triple i686-pc-win32 -verify -ast-print -DKW=struct \
+//   RUN:            -DBASES=' : B' -xc++ %s > %t.cpp
+//   RUN: FileCheck --check-prefixes=CHECK,PRINT,PRINT-CXX -DKW=struct \
+//   RUN:           -DBASES=' : B' %s --input-file %t.cpp
+//
+//   RUN: cat %t.diags >> %t.cpp
+//   RUN: %clang_cc1 -triple i686-pc-win32 -verify -ast-print %t.cpp \
 //   RUN: | FileCheck --check-prefixes=CHECK,PRINT,PRINT-CXX -DKW=struct \
 //   RUN:             -DBASES=' : B' %s
 
 // END.
 
 #ifndef KW
 # error KW undefined
 # define KW struct // help syntax checkers
void inInit() {
   // PRINT-NEXT:   long i;
   // PRINT-NEXT: } t2 = {sizeof([[KW]] T1)};
   KW T2 { long i; } t2 = {sizeof(KW T1)};
 }
 
 #ifdef __cplusplus
 // PRINT-CXX-LABEL: inMemberPtr
 void inMemberPtr() {
+  // Under windows, the implicit attribute __single_inheritance used to print
+  // between KW and T1 here, but that wasn't faithful to the original source.
+  //
   // PRINT-CXX-NEXT: [[KW]] T1 {
   // PRINT-CXX-NEXT:   int i;
   // PRINT-CXX-NEXT: };
   KW T1 { int i; };
   // PRINT-CXX-NEXT: [[KW]] T2 {
   // PRINT-CXX-NEXT: } T1::*p;
   KW T2 {} T1::*p;
 }