Instead of include location use included filename location in

GetIncludeNameAsTyped. In case of macro use spelling location (issue #67).

iwyu_location_util.cc

@@ -36,6 +36,22 @@ using clang::UnresolvedMemberExpr;
 
 namespace include_what_you_use {
 
+// Instead of returning spelling location of 'macro_loc', obtain expansion info
+// for macro at this location and return spelling location of expansion info.
+SourceLocation GetMacroStartSpellingLoc(SourceLocation macro_loc) {
+  CHECK_(macro_loc.isValid() && macro_loc.isMacroID()
+         && "Must call GetMacroStartSpellingLoc with valid macro location");
+  std::pair<clang::FileID, unsigned> macro_loc_info =
+      GlobalSourceManager()->getDecomposedLoc(macro_loc);
+  bool invalid = false;
+  const clang::SrcMgr::SLocEntry& loc_entry =
+      GlobalSourceManager()->getSLocEntry(macro_loc_info.first, &invalid);
+  CHECK_(!invalid && loc_entry.isExpansion()
+         && "Should be able to obtain expansion info for macro location");
+  const clang::SrcMgr::ExpansionInfo& expansion_info = loc_entry.getExpansion();
+  return expansion_info.getSpellingLoc();
+}
+
 // This works around two bugs(?) in clang where decl->getLocation()
 // can be wrong for implicit template instantiations and functions.
 // (1) Consider the following code:

iwyu_location_util.h

@@ -122,6 +122,10 @@ inline int GetLineNumber(clang::SourceLocation loc) {
   return retval;
 }
 
+// For macro at macro_loc returns spelling location of macro start.
+// macro_loc can point anywhere in macro.
+clang::SourceLocation GetMacroStartSpellingLoc(clang::SourceLocation macro_loc);
+
 // The rest of this section of the file is for returning the
 // FileEntry* corresponding to a source location: the file that the
 // location is in.  This is a surprising amount of work.

iwyu_preprocessor.cc

@@ -36,11 +36,11 @@ using clang::FileEntry;
 using clang::FileID;
 using clang::MacroInfo;
 using clang::Preprocessor;
-using clang::PresumedLoc;
 using clang::SourceLocation;
 using clang::SourceRange;
 using clang::Token;
 using llvm::errs;
+using llvm::StringRef;
 using std::make_pair;
 using std::string;
 
@@ -590,6 +590,21 @@ void IwyuPreprocessorInfo::Ifndef(SourceLocation loc, const Token& id) {
   FindAndReportMacroUse(GetName(id), id.getLocation());
 }
 
+void IwyuPreprocessorInfo::InclusionDirective(
+    SourceLocation hash_loc,
+    const Token& include_token,
+    StringRef filename,
+    bool is_angled,
+    const FileEntry* file,
+    SourceLocation last_include_token_loc,
+    StringRef search_path,
+    StringRef relative_path) {
+  if (last_include_token_loc.isMacroID())
+    include_filename_loc_ = GetMacroStartSpellingLoc(last_include_token_loc);
+  else
+    include_filename_loc_ = last_include_token_loc;
+}
+
 void IwyuPreprocessorInfo::FileChanged(SourceLocation loc,
                                        FileChangeReason reason,
                                        SrcMgr::CharacteristicKind file_type,
@@ -619,8 +634,12 @@ void IwyuPreprocessorInfo::FileChanged(SourceLocation loc,
 void IwyuPreprocessorInfo::FileSkipped(const FileEntry& file,
                                        const Token &filename,
                                        SrcMgr::CharacteristicKind file_type) {
-  const SourceLocation include_loc = filename.getLocation();
-  const string include_name_as_typed = GetIncludeNameAsTyped(include_loc);
+  CHECK_(include_filename_loc_.isValid() &&
+         "Must skip file only for actual inclusion directive");
+  const string include_name_as_typed =
+      GetIncludeNameAsTyped(include_filename_loc_);
+  const SourceLocation include_loc =
+      GetInstantiationLoc(filename.getLocation());
   ERRSYM(GetFileEntry(include_loc))
       << "[ (#include)  ] " << include_name_as_typed
       << " (" << GetFilePath(&file) << ")\n";
@@ -633,12 +652,13 @@ void IwyuPreprocessorInfo::FileChanged_EnterFile(
     SourceLocation file_beginning) {
   // Get the location of the #include directive that resulted in the
   // include of the file that file_beginning is in.
-  const PresumedLoc presumed =
-      GlobalSourceManager()->getPresumedLoc(file_beginning);
-  const SourceLocation include_loc = presumed.getIncludeLoc();
+  const SourceLocation include_loc = GlobalSourceManager()->getIncludeLoc(
+      GlobalSourceManager()->getFileID(file_beginning));
   string include_name_as_typed = "";
   if (!IsBuiltinOrCommandLineFile(GetFileEntry(include_loc))) {
-    include_name_as_typed = GetIncludeNameAsTyped(include_loc);
+    CHECK_(include_filename_loc_.isValid() &&
+           "Include from not built-in file must have inclusion directive");
+    include_name_as_typed = GetIncludeNameAsTyped(include_filename_loc_);
   }
   ERRSYM(GetFileEntry(include_loc))
       << "[ #include    ] " << include_name_as_typed

iwyu_preprocessor.h

@@ -185,6 +185,15 @@ class IwyuPreprocessorInfo : public clang::PPCallbacks,
   // virtual void Else();
   // virtual void Endif();
 
+  virtual void InclusionDirective(clang::SourceLocation hash_loc,
+                                 const clang::Token& include_token,
+                                 llvm::StringRef filename,
+                                 bool is_angled,
+                                 const clang::FileEntry* file,
+                                 clang::SourceLocation last_include_token_loc,
+                                 llvm::StringRef search_path,
+                                 llvm::StringRef relative_path);
+
   virtual void FileChanged(clang::SourceLocation loc, FileChangeReason reason,
                            clang::SrcMgr::CharacteristicKind file_type,
                            clang::FileID PrevFID);
@@ -331,6 +340,13 @@ class IwyuPreprocessorInfo : public clang::PPCallbacks,
   // "begin_exports".  There should be at most one item in this stack
   // per file in the current inclusion chain..
   stack<clang::SourceLocation> begin_exports_location_stack_;
+
+  // Filename spelling location in the last encountered inclusion directive.
+  // Should be used only in FileChanged_EnterFile, FileSkipped when
+  // corresponding callback is caused by inclusion directive.  Don't use in
+  // other places because it is unclear which inclusion directive filename
+  // location corresponds to.
+  clang::SourceLocation include_filename_loc_;
 };
 
 }  // namespace include_what_you_use

tests/computed_include.cc

@@ -0,0 +1,46 @@
+//===--- computed_include.cc - test input file for iwyu -------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// Tests computed #includes, i.e. #includes with macros.
+
+#include "tests/computed_include.h"
+
+// Test macro defined in another file.
+#include MACRO_INC
+// Test when #include with macro from another file is skipped.
+#include MACRO_INC
+
+// Macros with angle brackets differ from macros with quotation marks: the last
+// include token is '>' and '"foo.h"' respectively.
+#define MACRO_ANGLED_INC <stdio.h>
+#include MACRO_ANGLED_INC
+// And test how such #include is skipped.
+#include MACRO_ANGLED_INC
+
+// Test macro with arguments.
+#define STRINGIZE(x) #x
+#include STRINGIZE(tests/computed_include.h)
+
+IndirectClass ic;
+
+/**** IWYU_SUMMARY
+
+tests/computed_include.cc should add these lines:
+
+tests/computed_include.cc should remove these lines:
+- #include "tests/computed_include.h"  // lines XX-XX
+- #include <stdio.h>  // lines XX-XX
+- #include <stdio.h>  // lines XX-XX
+- #include "tests/indirect.h"  // lines XX-XX
+
+The full include-list for tests/computed_include.cc:
+#include "tests/computed_include.h"
+#include "tests/indirect.h"  // for IndirectClass
+
+***** IWYU_SUMMARY */

tests/computed_include.h

@@ -0,0 +1,16 @@
+//===--- computed_include.h - test input file for iwyu --------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#define MACRO_INC "tests/indirect.h"
+
+/**** IWYU_SUMMARY
+
+(tests/computed_include.h has correct #includes/fwd-decls)
+
+***** IWYU_SUMMARY */