diff --git a/include/llvm/ModuleProvider.h b/include/llvm/ModuleProvider.h
index 2f185e01d35..b42a5036e5c 100644
--- a/include/llvm/ModuleProvider.h
+++ b/include/llvm/ModuleProvider.h
@@ -18,6 +18,8 @@
 #ifndef MODULEPROVIDER_H
 #define MODULEPROVIDER_H
 
+#include <string>
+
 namespace llvm {
 
 class Function;
@@ -35,22 +37,24 @@ public:
   ///
   Module* getModule() { return TheModule; }
 
-  /// materializeFunction - make sure the given function is fully read.  Note
-  /// that this can throw an exception if the module is corrupt!
+  /// materializeFunction - make sure the given function is fully read.  If the
+  /// module is corrupt, this returns true and fills in the optional string
+  /// with information about the problem.  If successful, this returns false.
   ///
-  virtual void materializeFunction(Function *F) = 0;
+  virtual bool materializeFunction(Function *F, std::string *ErrInfo = 0) = 0;
 
   /// materializeModule - make sure the entire Module has been completely read.
-  /// Note that this can throw an exception if the module is corrupt!
+  /// On error, return null and fill in the error string if specified.
   ///
-  virtual Module* materializeModule() = 0;
+  virtual Module* materializeModule(std::string *ErrInfo = 0) = 0;
 
   /// releaseModule - no longer delete the Module* when provider is destroyed.
-  /// Note that this can throw an exception if the module is corrupt!
+  /// On error, return null and fill in the error string if specified.
   ///
-  virtual Module* releaseModule() {
+  virtual Module* releaseModule(std::string *ErrInfo = 0) {
     // Since we're losing control of this Module, we must hand it back complete
-    materializeModule();
+    if (materializeModule(ErrInfo))
+      return 0;
     Module *tempM = TheModule;
     TheModule = 0;
     return tempM;
@@ -66,8 +70,10 @@ struct ExistingModuleProvider : public ModuleProvider {
   ExistingModuleProvider(Module *M) {
     TheModule = M;
   }
-  void materializeFunction(Function *F) {}
-  Module* materializeModule() { return TheModule; }
+  bool materializeFunction(Function *F, std::string *ErrInfo = 0) {
+    return false;
+  }
+  Module* materializeModule(std::string *ErrInfo = 0) { return TheModule; }
 };
 
 } // End llvm namespace
diff --git a/lib/Bytecode/Reader/Reader.h b/lib/Bytecode/Reader/Reader.h
index ffc251b64ef..9cecf52436f 100644
--- a/lib/Bytecode/Reader/Reader.h
+++ b/lib/Bytecode/Reader/Reader.h
@@ -153,18 +153,33 @@ public:
   /// implementation is identical to the ParseFunction method.
   /// @see ParseFunction
   /// @brief Make a specific function materialize.
-  virtual void materializeFunction(Function *F) {
+  virtual bool materializeFunction(Function *F, std::string *ErrInfo = 0) {
     LazyFunctionMap::iterator Fi = LazyFunctionLoadMap.find(F);
-    if (Fi == LazyFunctionLoadMap.end()) return;
-    ParseFunction(F);
+    if (Fi == LazyFunctionLoadMap.end()) return false;
+    try {
+      ParseFunction(F);
+    } catch (std::string &ErrStr) {
+      if (ErrInfo) *ErrInfo = ErrStr;
+      return true;
+    } catch (...) {
+      return true;
+    }
+    return false;
   }
 
   /// This method is abstract in the parent ModuleProvider class. Its
   /// implementation is identical to ParseAllFunctionBodies.
   /// @see ParseAllFunctionBodies
   /// @brief Make the whole module materialize
-  virtual Module* materializeModule() {
-    ParseAllFunctionBodies();
+  virtual Module* materializeModule(std::string *ErrInfo = 0) {
+    try {
+      ParseAllFunctionBodies();
+    } catch (std::string &ErrStr) {
+      if (ErrInfo) *ErrInfo = ErrStr;
+      return 0;
+    } catch (...) {
+      return 0;
+    }
     return TheModule;
   }
 
diff --git a/lib/Bytecode/Reader/ReaderWrappers.cpp b/lib/Bytecode/Reader/ReaderWrappers.cpp
index 956d1ede696..b9e7cd29aac 100644
--- a/lib/Bytecode/Reader/ReaderWrappers.cpp
+++ b/lib/Bytecode/Reader/ReaderWrappers.cpp
@@ -170,7 +170,8 @@ static ModuleProvider* CheckVarargs(ModuleProvider* MP) {
 
   // If we get to this point, we know that we have an old-style module.
   // Materialize the whole thing to perform the rewriting.
-  MP->materializeModule();
+  if (MP->materializeModule() == 0)
+    return 0;
 
   if(Function* F = M->getNamedFunction("llvm.va_start")) {
     assert(F->arg_size() == 0 && "Obsolete va_start takes 0 argument!");
@@ -376,22 +377,18 @@ static void getSymbols(Module*M, std::vector<std::string>& symbols) {
 // Get just the externally visible defined symbols from the bytecode
 bool llvm::GetBytecodeSymbols(const sys::Path& fName,
                               std::vector<std::string>& symbols) {
-  try {
-    std::auto_ptr<ModuleProvider> AMP(
-        getBytecodeModuleProvider(fName.toString()));
+  std::auto_ptr<ModuleProvider> AMP(
+      getBytecodeModuleProvider(fName.toString()));
 
-    // Get the module from the provider
-    Module* M = AMP->materializeModule();
+  // Get the module from the provider
+  Module* M = AMP->materializeModule();
+  if (M == 0) return false;
 
-    // Get the symbols
-    getSymbols(M, symbols);
+  // Get the symbols
+  getSymbols(M, symbols);
 
-    // Done with the module
-    return true;
-
-  } catch (...) {
-    return false;
-  }
+  // Done with the module
+  return true;
 }
 
 ModuleProvider*
@@ -406,6 +403,7 @@ llvm::GetBytecodeSymbols(const unsigned char*Buffer, unsigned Length,
 
     // Get the module from the provider
     Module* M = MP->materializeModule();
+    if (M == 0) return 0;
 
     // Get the symbols
     getSymbols(M, symbols);
diff --git a/lib/VMCore/Pass.cpp b/lib/VMCore/Pass.cpp
index a7160f1f1ee..dc49ac6aeec 100644
--- a/lib/VMCore/Pass.cpp
+++ b/lib/VMCore/Pass.cpp
@@ -95,14 +95,10 @@ FunctionPassManager::~FunctionPassManager() { delete PM; }
 void FunctionPassManager::add(FunctionPass *P) { PM->add(P); }
 void FunctionPassManager::add(ImmutablePass *IP) { PM->add(IP); }
 bool FunctionPassManager::run(Function &F) {
-  try {
-    MP->materializeFunction(&F);
-  } catch (std::string& errstr) {
+  std::string errstr;
+  if (MP->materializeFunction(&F, &errstr)) {
     std::cerr << "Error reading bytecode file: " << errstr << "\n";
     abort();
-  } catch (...) {
-    std::cerr << "Error reading bytecode file!\n";
-    abort();
   }
   return PM->run(F);
 }