[llvm] r194844 - Readobj: If NumbersOfSections is 0xffff, it's an COFF import library.

[Rui Ueyama]

Author: ruiu
Date: Fri Nov 15 14:23:25 2013
New Revision: 194844

URL: http://llvm.org/viewvc/llvm-project?rev=194844&view=rev
Log:
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.

Modified:
    llvm/trunk/include/llvm/Object/COFF.h
    llvm/trunk/lib/Object/COFFObjectFile.cpp

Modified: llvm/trunk/include/llvm/Object/COFF.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Object/COFF.h?rev=194844&r1=194843&r2=194844&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Object/COFF.h (original)
+++ llvm/trunk/include/llvm/Object/COFF.h Fri Nov 15 14:23:25 2013
@@ -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.

Modified: llvm/trunk/lib/Object/COFFObjectFile.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Object/COFFObjectFile.cpp?rev=194844&r1=194843&r2=194844&view=diff
==============================================================================
--- llvm/trunk/lib/Object/COFFObjectFile.cpp (original)
+++ llvm/trunk/lib/Object/COFFObjectFile.cpp Fri Nov 15 14:23:25 2013
@@ -507,9 +507,10 @@ COFFObjectFile::COFFObjectFile(MemoryBuf
     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_s
 
 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));
 }