r361376 - [Frontend] Return an error on bad inputs to PrecompiledPreabmle

[Ilya Biryukov via cfe-commits]

Author: ibiryukov
Date: Wed May 22 05:50:01 2019
New Revision: 361376

URL: http://llvm.org/viewvc/llvm-project?rev=361376&view=rev
Log:
[Frontend] Return an error on bad inputs to PrecompiledPreabmle

Summary:
Instead of failing with assertions. Fixes a crash found by oss-fuzz:
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=12865

Reviewers: sammccall

Reviewed By: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D62137

Modified:
    cfe/trunk/include/clang/Frontend/PrecompiledPreamble.h
    cfe/trunk/lib/Frontend/ASTUnit.cpp
    cfe/trunk/lib/Frontend/PrecompiledPreamble.cpp

Modified: cfe/trunk/include/clang/Frontend/PrecompiledPreamble.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Frontend/PrecompiledPreamble.h?rev=361376&r1=361375&r2=361376&view=diff
==============================================================================
--- cfe/trunk/include/clang/Frontend/PrecompiledPreamble.h (original)
+++ cfe/trunk/include/clang/Frontend/PrecompiledPreamble.h Wed May 22 05:50:01 2019
@@ -291,7 +291,8 @@ enum class BuildPreambleError {
   CouldntCreateTempFile = 1,
   CouldntCreateTargetInfo,
   BeginSourceFileFailed,
-  CouldntEmitPCH
+  CouldntEmitPCH,
+  BadInputs
 };
 
 class BuildPreambleErrorCategory final : public std::error_category {

Modified: cfe/trunk/lib/Frontend/ASTUnit.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Frontend/ASTUnit.cpp?rev=361376&r1=361375&r2=361376&view=diff
==============================================================================
--- cfe/trunk/lib/Frontend/ASTUnit.cpp (original)
+++ cfe/trunk/lib/Frontend/ASTUnit.cpp Wed May 22 05:50:01 2019
@@ -1368,6 +1368,7 @@ ASTUnit::getMainBufferWithPrecompiledPre
       case BuildPreambleError::CouldntCreateTargetInfo:
       case BuildPreambleError::BeginSourceFileFailed:
       case BuildPreambleError::CouldntEmitPCH:
+      case BuildPreambleError::BadInputs:
         // These erros are more likely to repeat, retry after some period.
         PreambleRebuildCountdown = DefaultPreambleRebuildInterval;
         return nullptr;

Modified: cfe/trunk/lib/Frontend/PrecompiledPreamble.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Frontend/PrecompiledPreamble.cpp?rev=361376&r1=361375&r2=361376&view=diff
==============================================================================
--- cfe/trunk/lib/Frontend/PrecompiledPreamble.cpp (original)
+++ cfe/trunk/lib/Frontend/PrecompiledPreamble.cpp Wed May 22 05:50:01 2019
@@ -299,14 +299,13 @@ llvm::ErrorOr<PrecompiledPreamble> Preco
   // created. This complexity should be lifted elsewhere.
   Clang->getTarget().adjust(Clang->getLangOpts());
 
-  assert(Clang->getFrontendOpts().Inputs.size() == 1 &&
-         "Invocation must have exactly one source file!");
-  assert(Clang->getFrontendOpts().Inputs[0].getKind().getFormat() ==
-             InputKind::Source &&
-         "FIXME: AST inputs not yet supported here!");
-  assert(Clang->getFrontendOpts().Inputs[0].getKind().getLanguage() !=
-             InputKind::LLVM_IR &&
-         "IR inputs not support here!");
+  if (Clang->getFrontendOpts().Inputs.size() != 1 ||
+      Clang->getFrontendOpts().Inputs[0].getKind().getFormat() !=
+          InputKind::Source ||
+      Clang->getFrontendOpts().Inputs[0].getKind().getLanguage() ==
+          InputKind::LLVM_IR) {
+    return BuildPreambleError::BadInputs;
+  }
 
   // Clear out old caches and data.
   Diagnostics.Reset();
@@ -784,6 +783,8 @@ std::string BuildPreambleErrorCategory::
     return "BeginSourceFile() return an error";
   case BuildPreambleError::CouldntEmitPCH:
     return "Could not emit PCH";
+  case BuildPreambleError::BadInputs:
+    return "Command line arguments must contain exactly one source file";
   }
   llvm_unreachable("unexpected BuildPreambleError");
 }