From: Devang Patel <dpatel@apple.com>
Date: Tue, 16 Jun 2009 18:02:02 +0000 (+0000)
Subject: It is possible that main input file does not have any symbol with debug info. To... 
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=998316908cf1f0d50257dcaf60dc8154a1e294c9;p=clang

It is possible that main input file does not have any symbol with debug info. To  handle this edge case, always create main compile unit first.
This fixes PR 4228.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@73520 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/CGDebugInfo.cpp b/lib/CodeGen/CGDebugInfo.cpp
index 049e716c7c..1f17692a1d 100644
--- a/lib/CodeGen/CGDebugInfo.cpp
+++ b/lib/CodeGen/CGDebugInfo.cpp
@@ -50,6 +50,24 @@ void CGDebugInfo::setLocation(SourceLocation Loc) {
 /// getOrCreateCompileUnit - Get the compile unit from the cache or create a new
 /// one if necessary. This returns null for invalid source locations.
 llvm::DICompileUnit CGDebugInfo::getOrCreateCompileUnit(SourceLocation Loc) {
+
+  // Each input file is encoded as a separate compile unit in LLVM
+  // debugging information output. However, many target specific tool chains
+  // prefer to encode only one compile unit in an object file. In this 
+  // situation, the LLVM code generator will include  debugging information
+  // entities in the compile unit that is marked as main compile unit. The 
+  // code generator accepts maximum one main compile unit per module. If a
+  // module does not contain any main compile unit then the code generator 
+  // will emit multiple compile units in the output object file. Create main
+  // compile unit if there is not one available.
+  const LangOptions &LO = M->getLangOptions();
+  if (isMainCompileUnitCreated == false) {
+    if (LO.getMainFileName()) {
+      createCompileUnit(LO.getMainFileName(), true /* isMain */);
+      isMainCompileUnitCreated = true;
+    }
+  }
+
   // Get source file information.
   const char *FileName =  "<unknown>";
   SourceManager &SM = M->getContext().getSourceManager();
@@ -72,25 +90,26 @@ llvm::DICompileUnit CGDebugInfo::getOrCreateCompileUnit(SourceLocation Loc) {
     AbsFileName = tmp;
   }
 
-  // See if thie compile unit is representing main source file. Each source
-  // file has corresponding compile unit. There is only one main source
-  // file at a time.
-  bool isMain = false;
-  const LangOptions &LO = M->getLangOptions();
-  const char *MainFileName = LO.getMainFileName();
-  if (isMainCompileUnitCreated == false) {
-    if (MainFileName) {
-      if (!strcmp(AbsFileName.getLast().c_str(), MainFileName))
-        isMain = true;
-    } else {
-      if (Loc.isValid() && SM.isFromMainFile(Loc))
-        isMain = true;
-    }
-    if (isMain)
-      isMainCompileUnitCreated = true;
+  // There is only one main source file at a time whose compile unit
+  // is already created.
+  Unit = createCompileUnit(FileName, false /* isMain */);
+  return Unit;
+}
+
+/// createCompileUnit - Create a new unit for the given file.
+llvm::DICompileUnit CGDebugInfo::createCompileUnit(const char *FileName,
+                                                   bool isMain) {
+
+  // Get absolute path name.
+  llvm::sys::Path AbsFileName(FileName);
+  if (!AbsFileName.isAbsolute()) {
+    llvm::sys::Path tmp = llvm::sys::Path::GetCurrentDirectory();
+    tmp.appendComponent(FileName);
+    AbsFileName = tmp;
   }
 
   unsigned LangTag;
+  const LangOptions &LO = M->getLangOptions();
   if (LO.CPlusPlus) {
     if (LO.ObjC1)
       LangTag = llvm::dwarf::DW_LANG_ObjC_plus_plus;
@@ -114,12 +133,13 @@ llvm::DICompileUnit CGDebugInfo::getOrCreateCompileUnit(SourceLocation Loc) {
     RuntimeVers = LO.ObjCNonFragileABI ? 2 : 1;
   
   // Create new compile unit.
-  return Unit = DebugFactory.CreateCompileUnit(LangTag, AbsFileName.getLast(),
-                                               AbsFileName.getDirname(), 
-                                               Producer, isMain, isOptimized,
-                                               Flags, RuntimeVers);
+  return DebugFactory.CreateCompileUnit(LangTag, AbsFileName.getLast(),
+                                        AbsFileName.getDirname(), 
+                                        Producer, isMain, isOptimized,
+                                        Flags, RuntimeVers);
 }
 
+
 /// CreateType - Get the Basic type from the cache or create a new
 /// one if necessary.
 llvm::DIType CGDebugInfo::CreateType(const BuiltinType *BT,
diff --git a/lib/CodeGen/CGDebugInfo.h b/lib/CodeGen/CGDebugInfo.h
index de655800fa..8f3368e4eb 100644
--- a/lib/CodeGen/CGDebugInfo.h
+++ b/lib/CodeGen/CGDebugInfo.h
@@ -111,7 +111,9 @@ private:
   void EmitDeclare(const VarDecl *decl, unsigned Tag, llvm::Value *AI,
                    CGBuilderTy &Builder);
   
-  
+  /// createCompileUnit - Create a new unit for the given file.
+  llvm::DICompileUnit createCompileUnit(const char *FileName, bool isMain);
+
   /// getOrCreateCompileUnit - Get the compile unit from the cache or create a
   /// new one if necessary.
   llvm::DICompileUnit getOrCreateCompileUnit(SourceLocation Loc);
diff --git a/test/CodeGen/2009-06-16-inc_test.c b/test/CodeGen/2009-06-16-inc_test.c
new file mode 100644
index 0000000000..b28f63a1c5
--- /dev/null
+++ b/test/CodeGen/2009-06-16-inc_test.c
@@ -0,0 +1,3 @@
+// RUN: clang -c -g %s -o /dev/null
+// PR 4228 
+#include "2009-06-16-test.c"
diff --git a/test/CodeGen/2009-06-16-test.c b/test/CodeGen/2009-06-16-test.c
new file mode 100644
index 0000000000..4189d06812
--- /dev/null
+++ b/test/CodeGen/2009-06-16-test.c
@@ -0,0 +1,15 @@
+
+#ifndef TEST
+#define TEST
+#define INSIDE_RECURSION
+#include "2009-06-16-test.c"
+#undef INSIDE_RECURSION
+#endif
+
+#ifndef INSIDE_RECURSION
+int i;
+#endif
+
+#ifdef INSIDE_RECURSION
+int j;
+#endif