commit dac39857d6545e32f20f0735a04b934f36b6c1d9
author David Majnemer <david.majnemer@gmail.com> Fri Sep 26 22:32:16 2014 +0000
committer David Majnemer <david.majnemer@gmail.com> Fri Sep 26 22:32:16 2014 +0000
tree a969577804c80a12810628209ad39403b5edd65b
parent b774a0e75071f4b32e741297b4e017615b01a8a9

Object: BSS/virtual sections don't have contents

Users of getSectionContents shouldn't try to pass in BSS or virtual
sections.  In all instances, this is a bug in the code calling this
routine.

N.B. Some COFF implementations (like CL) will mark their BSS sections as
taking space on disk.  This would confuse COFFObjectFile into thinking
the section is larger than the file.

llvm-svn: 218549

llvm/tools/llvm-readobj/COFFDumper.cpp

diff --git a/llvm/tools/llvm-readobj/COFFDumper.cpp b/llvm/tools/llvm-readobj/COFFDumper.cpp
index 99a374d..3d71d83 100644
--- a/llvm/tools/llvm-readobj/COFFDumper.cpp
+++ b/llvm/tools/llvm-readobj/COFFDumper.cpp
@@ -635,7 +635,8 @@
     if (Name == ".debug$S" && opts::CodeViewLineTables)
       printCodeViewLineTables(Sec);
 
-    if (opts::SectionData) {
+    if (opts::SectionData &&
+        !(Section->Characteristics & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA)) {
       StringRef Data;
       if (error(Sec.getContents(Data)))
         break;

llvm/tools/llvm-readobj/ELFDumper.cpp

diff --git a/llvm/tools/llvm-readobj/ELFDumper.cpp b/llvm/tools/llvm-readobj/ELFDumper.cpp
index 1791f5a..6da3318 100644
--- a/llvm/tools/llvm-readobj/ELFDumper.cpp
+++ b/llvm/tools/llvm-readobj/ELFDumper.cpp
@@ -604,7 +604,7 @@
       }
     }
 
-    if (opts::SectionData) {
+    if (opts::SectionData && Section->sh_type != ELF::SHT_NOBITS) {
       ArrayRef<uint8_t> Data = errorOrDefault(Obj->getSectionContents(Section));
       W.printBinaryBlock("SectionData",
                          StringRef((const char *)Data.data(), Data.size()));

llvm/tools/llvm-readobj/MachODumper.cpp

diff --git a/llvm/tools/llvm-readobj/MachODumper.cpp b/llvm/tools/llvm-readobj/MachODumper.cpp
index 41a78e7..2d09282 100644
--- a/llvm/tools/llvm-readobj/MachODumper.cpp
+++ b/llvm/tools/llvm-readobj/MachODumper.cpp
@@ -266,11 +266,16 @@
     }
 
     if (opts::SectionData) {
-      StringRef Data;
-      if (error(Section.getContents(Data)))
+      bool IsBSS;
+      if (error(Section.isBSS(IsBSS)))
         break;
+      if (!IsBSS) {
+        StringRef Data;
+        if (error(Section.getContents(Data)))
+          break;
 
-      W.printBinaryBlock("SectionData", Data);
+        W.printBinaryBlock("SectionData", Data);
+      }
     }
   }
 }