Readobj: If NumbersOfSections is 0xffff, it's an COFF import library.

0xffff does not mean that there are 65535 sections in a COFF file but
indicates that it's a COFF import library. This patch fixes SEGV error
when an import library file is passed to llvm-readobj.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194844 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/Object/COFF.h b/include/llvm/Object/COFF.h
index ec8998c7465cea5290b3262fa7c37fc268a8683e..e05ae6c654c74079746e6b9a7a6d2e569bf80bdc 100644 (file)
--- a/include/llvm/Object/COFF.h
+++ b/include/llvm/Object/COFF.h
@@ -57,6 +57,8 @@ struct coff_file_header {
   support::ulittle32_t NumberOfSymbols;
   support::ulittle16_t SizeOfOptionalHeader;
   support::ulittle16_t Characteristics;
+
+  bool isImportLibrary() const { return NumberOfSections == 0xffff; }
 };
 
 /// The 32-bit PE header that follows the COFF header.

diff --git a/lib/Object/COFFObjectFile.cpp b/lib/Object/COFFObjectFile.cpp
index f33caee33495ba5c3aa5282e4a50c35a8bb81d65..42066c372b43b5077a5de4c1099735ac3770f453 100644 (file)
--- a/lib/Object/COFFObjectFile.cpp
+++ b/lib/Object/COFFObjectFile.cpp
@@ -507,9 +507,10 @@ COFFObjectFile::COFFObjectFile(MemoryBuffer *Object, error_code &ec)
     CurPtr += COFFHeader->SizeOfOptionalHeader;
   }
 
-  if ((ec = getObject(SectionTable, Data, base() + CurPtr,
-                      COFFHeader->NumberOfSections * sizeof(coff_section))))
-    return;
+  if (!COFFHeader->isImportLibrary())
+    if ((ec = getObject(SectionTable, Data, base() + CurPtr,
+                        COFFHeader->NumberOfSections * sizeof(coff_section))))
+      return;
 
   // Initialize the pointer to the symbol table.
   if (COFFHeader->PointerToSymbolTable != 0)
@@ -586,7 +587,9 @@ section_iterator COFFObjectFile::begin_sections() const {
 
 section_iterator COFFObjectFile::end_sections() const {
   DataRefImpl ret;
-  ret.p = reinterpret_cast<uintptr_t>(SectionTable + COFFHeader->NumberOfSections);
+  int numSections = COFFHeader->isImportLibrary()
+      ? 0 : COFFHeader->NumberOfSections;
+  ret.p = reinterpret_cast<uintptr_t>(SectionTable + numSections);
   return section_iterator(SectionRef(ret, this));
 }