From: Rui Ueyama <ruiu@google.com>
Date: Thu, 14 Nov 2013 22:09:08 +0000 (+0000)
Subject: Recognize 0x0000 as a COFF file magic.
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=b850a05f2c914fef74dbafbf61470512a976c632;p=oota-llvm.git

Recognize 0x0000 as a COFF file magic.

Summary:
Some machine-type-neutral object files containing only undefined symbols
actually do exist in the Windows standard library. Need to recognize them
as COFF files.

Reviewers: Bigcheese

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D2164

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194734 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Support/Path.cpp b/lib/Support/Path.cpp
index 7fc9ab89672..dfa18aaa6d2 100644
--- a/lib/Support/Path.cpp
+++ b/lib/Support/Path.cpp
@@ -853,6 +853,9 @@ error_code has_magic(const Twine &path, const Twine &magic, bool &result) {
       if (Magic.size() >= sizeof(Expected) &&
           memcmp(Magic.data(), Expected, sizeof(Expected)) == 0)
         return file_magic::windows_resource;
+      // 0x0000 = COFF unknown machine type
+      if (Magic[1] == 0)
+        return file_magic::coff_object;
       break;
     }
     case 0xDE:  // 0x0B17C0DE = BC wraper
diff --git a/test/tools/llvm-readobj/Inputs/magic.coff-unknown b/test/tools/llvm-readobj/Inputs/magic.coff-unknown
new file mode 100644
index 00000000000..7b3b4619a8c
Binary files /dev/null and b/test/tools/llvm-readobj/Inputs/magic.coff-unknown differ
diff --git a/test/tools/llvm-readobj/file-headers.test b/test/tools/llvm-readobj/file-headers.test
index b900e365f20..d88029adddf 100644
--- a/test/tools/llvm-readobj/file-headers.test
+++ b/test/tools/llvm-readobj/file-headers.test
@@ -8,6 +8,8 @@ RUN: llvm-readobj -h %p/Inputs/trivial.obj.elf-i386 \
 RUN:   | FileCheck %s -check-prefix ELF32
 RUN: llvm-readobj -h %p/Inputs/trivial.obj.elf-x86-64 \
 RUN:   | FileCheck %s -check-prefix ELF64
+RUN: llvm-readobj -h %p/Inputs/magic.coff-unknown \
+RUN:   | FileCheck %s -check-prefix COFF-UNKNOWN
 
 COFF32:      File: {{(.*[/\\])?}}trivial.obj.coff-i386
 COFF32-NEXT: Format: COFF-i386
@@ -183,3 +185,17 @@ PE32-NEXT:     ReservedRVA: 0x0
 PE32-NEXT:     ReservedSize: 0x0
 PE32-NEXT:   }
 PE32-NEXT: }
+
+COFF-UNKNOWN:      Format: COFF-<unknown arch>
+COFF-UNKNOWN-NEXT: Arch: unknown
+COFF-UNKNOWN-NEXT: AddressSize: 32bit
+COFF-UNKNOWN-NEXT: ImageFileHeader {
+COFF-UNKNOWN-NEXT:   Machine: IMAGE_FILE_MACHINE_UNKNOWN (0x0)
+COFF-UNKNOWN-NEXT:   SectionCount: 3
+COFF-UNKNOWN-NEXT:   TimeDateStamp: 2013-11-14 21:19:28 (0x52853E60)
+COFF-UNKNOWN-NEXT:   PointerToSymbolTable: 0xF8
+COFF-UNKNOWN-NEXT:   SymbolCount: 11
+COFF-UNKNOWN-NEXT:   OptionalHeaderSize: 0
+COFF-UNKNOWN-NEXT:   Characteristics [ (0x0)
+COFF-UNKNOWN-NEXT:   ]
+COFF-UNKNOWN-NEXT: }
diff --git a/unittests/Support/Path.cpp b/unittests/Support/Path.cpp
index caf17b9b225..2323029b589 100644
--- a/unittests/Support/Path.cpp
+++ b/unittests/Support/Path.cpp
@@ -418,6 +418,7 @@ TEST_F(FileSystemTest, DirectoryIteration) {
 
 const char archive[] = "!<arch>\x0A";
 const char bitcode[] = "\xde\xc0\x17\x0b";
+const char coff_object[] = "\x00\x00......";
 const char elf_relocatable[] = { 0x7f, 'E', 'L', 'F', 1, 2, 1, 0, 0,
                                  0,    0,   0,   0,   0, 0, 0, 0, 1 };
 const char macho_universal_binary[] = "\xca\xfe\xba\xbe...\0x00";
@@ -445,6 +446,7 @@ TEST_F(FileSystemTest, Magic) {
     { #magic, magic, sizeof(magic), fs::file_magic::magic }
     DEFINE(archive),
     DEFINE(bitcode),
+    DEFINE(coff_object),
     DEFINE(elf_relocatable),
     DEFINE(macho_universal_binary),
     DEFINE(macho_object),