Fixed double-free in case of module loading error.

GetOutputStream() owns the stream it returns pointer to and the
pointer should never be freed by us. When we fail to load and exit
early, unique_ptr still holds the pointer and frees it which leads to
compiler crash when CompilerInstance attempts to free it again.

Added regression test for failed bitcode linking.

Differential Revision: http://reviews.llvm.org/D9625

llvm-svn: 237159

diff --git a/clang/lib/CodeGen/CodeGenAction.cpp b/clang/lib/CodeGen/CodeGenAction.cpp
index 075832f..7216f94 100644 (file)
--- a/clang/lib/CodeGen/CodeGenAction.cpp
+++ b/clang/lib/CodeGen/CodeGenAction.cpp
@@ -632,7 +632,7 @@ GetOutputStream(CompilerInstance &CI, StringRef InFile, BackendAction Action) {
 std::unique_ptr<ASTConsumer>
 CodeGenAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
   BackendAction BA = static_cast<BackendAction>(Act);
-  std::unique_ptr<raw_pwrite_stream> OS(GetOutputStream(CI, InFile, BA));
+  raw_pwrite_stream *OS = GetOutputStream(CI, InFile, BA);
   if (BA != Backend_EmitNothing && !OS)
     return nullptr;
 
@@ -669,7 +669,7 @@ CodeGenAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
   std::unique_ptr<BackendConsumer> Result(new BackendConsumer(
       BA, CI.getDiagnostics(), CI.getCodeGenOpts(), CI.getTargetOpts(),
       CI.getLangOpts(), CI.getFrontendOpts().ShowTimers, InFile,
-      LinkModuleToUse, OS.release(), *VMContext, CoverageInfo));
+      LinkModuleToUse, OS, *VMContext, CoverageInfo));
   BEConsumer = Result.get();
   return std::move(Result);
 }

diff --git a/clang/test/CodeGen/link-bitcode-file.c b/clang/test/CodeGen/link-bitcode-file.c
index fb97b4d..92b1a88 100644 (file)
--- a/clang/test/CodeGen/link-bitcode-file.c
+++ b/clang/test/CodeGen/link-bitcode-file.c
@@ -1,6 +1,9 @@
 // RUN: %clang_cc1 -triple i386-pc-linux-gnu -DBITCODE -emit-llvm-bc -o %t.bc %s
 // RUN: %clang_cc1 -triple i386-pc-linux-gnu -mlink-bitcode-file %t.bc -O3 -emit-llvm -o - %s | FileCheck -check-prefix=CHECK-NO-BC %s
 // RUN: not %clang_cc1 -triple i386-pc-linux-gnu -DBITCODE -mlink-bitcode-file %t.bc -O3 -emit-llvm -o - %s 2>&1 | FileCheck -check-prefix=CHECK-BC %s
+// Make sure we deal with failure to load the file.
+// RUN: not %clang_cc1 -triple i386-pc-linux-gnu -mlink-bitcode-file no-such-file.bc \
+// RUN:    -emit-llvm -o - %s 2>&1 | FileCheck -check-prefix=CHECK-NO-FILE %s
 
 int f(void);
 
@@ -22,3 +25,5 @@ int g(void) {
 // CHECK-NO-BC-LABEL: define i32 @f
 
 #endif
+
+// CHECK-NO-FILE: fatal error: cannot open file 'no-such-file.bc'