From a43da8254fec1e97522a57b74b7a8f8bb04d827c Mon Sep 17 00:00:00 2001 From: Alex Lorenz Date: Fri, 7 Jul 2017 10:25:12 +0000 Subject: [PATCH] [Frontend] Verify that the bitstream is not empty before reading the serialised diagnostics Clang should avoid calling report_fatal_error when the file with the serialised diagnostics is empty. This commit changes Clang's serialised diagnostic reader, now it reports an appropriate error instead of crashing. rdar://31939877 Differential Revision: https://reviews.llvm.org/D35069 git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@307384 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Frontend/SerializedDiagnosticReader.cpp | 3 +++ test/Index/Inputs/empty.dia | 0 test/Index/read-empty-diags.test | 2 ++ 3 files changed, 5 insertions(+) create mode 100644 test/Index/Inputs/empty.dia create mode 100644 test/Index/read-empty-diags.test diff --git a/lib/Frontend/SerializedDiagnosticReader.cpp b/lib/Frontend/SerializedDiagnosticReader.cpp index 8a8161488f..08b7087fba 100644 --- a/lib/Frontend/SerializedDiagnosticReader.cpp +++ b/lib/Frontend/SerializedDiagnosticReader.cpp @@ -27,6 +27,9 @@ std::error_code SerializedDiagnosticReader::readDiagnostics(StringRef File) { llvm::BitstreamCursor Stream(**Buffer); Optional BlockInfo; + if (Stream.AtEndOfStream()) + return SDError::InvalidSignature; + // Sniff for the signature. if (Stream.Read(8) != 'D' || Stream.Read(8) != 'I' || diff --git a/test/Index/Inputs/empty.dia b/test/Index/Inputs/empty.dia new file mode 100644 index 0000000000..e69de29bb2 diff --git a/test/Index/read-empty-diags.test b/test/Index/read-empty-diags.test new file mode 100644 index 0000000000..cef751c920 --- /dev/null +++ b/test/Index/read-empty-diags.test @@ -0,0 +1,2 @@ +// RUN: not c-index-test -read-diagnostics %S/Inputs/empty.dia 2>&1 | FileCheck %s +// CHECK: Trouble deserializing file (Invalid File): Invalid diagnostics signature