[llvm] r361631 - Revert r361630 "[llvm-readelf] - Allow dumping of the .dynamic section even if there is no PT_DYNAMIC header."

[George Rimar via llvm-commits]

Author: grimar
Date: Fri May 24 04:24:42 2019
New Revision: 361631

URL: http://llvm.org/viewvc/llvm-project?rev=361631&view=rev
Log:
Revert r361630 "[llvm-readelf] - Allow dumping of the .dynamic section even if there is no PT_DYNAMIC header."

It broke BB:
http://lab.llvm.org:8011/builders/ppc64le-lld-multistage-test/builds/3748

Modified:
    llvm/trunk/test/tools/llvm-readobj/elf-dynamic-no-pt-dynamic.test
    llvm/trunk/tools/llvm-readobj/ELFDumper.cpp

Modified: llvm/trunk/test/tools/llvm-readobj/elf-dynamic-no-pt-dynamic.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/tools/llvm-readobj/elf-dynamic-no-pt-dynamic.test?rev=361631&r1=361630&r2=361631&view=diff
==============================================================================
--- llvm/trunk/test/tools/llvm-readobj/elf-dynamic-no-pt-dynamic.test (original)
+++ llvm/trunk/test/tools/llvm-readobj/elf-dynamic-no-pt-dynamic.test Fri May 24 04:24:42 2019
@@ -1,23 +1,16 @@
-## Show that dumping occurs even if there is no PT_DYNAMIC header.
-## This is inconsistent with the GNU behavior, but seems to be more reasonable.
+# Show that no dumping occurs if there is no PT_DYNAMIC header.
 # RUN: yaml2obj %s -o %t.no-phdr
 # RUN: llvm-readobj --dynamic-table %t.no-phdr | FileCheck %s --check-prefix=LLVM
-# RUN: llvm-readelf --dynamic-table %t.no-phdr | FileCheck %s --check-prefix=GNU
+# RUN: llvm-readelf --dynamic-table %t.no-phdr | FileCheck %s --check-prefix=GNU --allow-empty
 
 # LLVM:      File: {{.*}}.no-phdr
 # LLVM-NEXT: Format: ELF64-x86-64
 # LLVM-NEXT: Arch: x86_64
 # LLVM-NEXT: AddressSize: 64bit
 # LLVM-NEXT: LoadName:{{ *}}
-# LLVM-NEXT: DynamicSection [ (1 entries)
-# LLVM-NEXT:   Tag                Type Name/Value
-# LLVM-NEXT:   0x0000000000000000 NULL 0x0
-# LLVM-NEXT: ]
+# LLVM-NOT:  {{.}}
 
-# GNU:      DynamicSection [ (1 entries)
-# GNU-NEXT:   Tag                Type Name/Value
-# GNU-NEXT:   0x0000000000000000 NULL 0x0
-# GNU-NEXT: ]
+# GNU-NOT: {{.}}
 
 --- !ELF
 FileHeader:

Modified: llvm/trunk/tools/llvm-readobj/ELFDumper.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/llvm-readobj/ELFDumper.cpp?rev=361631&r1=361630&r2=361631&view=diff
==============================================================================
--- llvm/trunk/tools/llvm-readobj/ELFDumper.cpp (original)
+++ llvm/trunk/tools/llvm-readobj/ELFDumper.cpp Fri May 24 04:24:42 2019
@@ -1331,7 +1331,6 @@ static const char *getElfMipsOptionsOdkT
 
 template <typename ELFT>
 void ELFDumper<ELFT>::loadDynamicTable(const ELFFile<ELFT> *Obj) {
-  // Try to locate the PT_DYNAMIC header.
   const Elf_Phdr *DynamicPhdr = nullptr;
   for (const Elf_Phdr &Phdr : unwrapOrError(Obj->program_headers())) {
     if (Phdr.p_type != ELF::PT_DYNAMIC)
@@ -1340,6 +1339,11 @@ void ELFDumper<ELFT>::loadDynamicTable(c
     break;
   }
 
+  // We do not want to dump dynamic section if we have no PT_DYNAMIC header.
+  // This matches GNU's behavior.
+  if (!DynamicPhdr)
+    return;
+
   // Try to locate the .dynamic section in the sections header table.
   const Elf_Shdr *DynamicSec = nullptr;
   for (const Elf_Shdr &Sec : unwrapOrError(Obj->sections())) {
@@ -1354,16 +1358,9 @@ void ELFDumper<ELFT>::loadDynamicTable(c
   // Ignore sh_entsize and use the expected value for entry size explicitly.
   // This allows us to dump the dynamic sections with a broken sh_entsize
   // field.
-  if (DynamicSec) {
+  if (DynamicSec)
     DynamicTable = checkDRI({ObjF->getELFFile()->base() + DynamicSec->sh_offset,
                              DynamicSec->sh_size, sizeof(Elf_Dyn)});
-    parseDynamicTable();
-  }
-
-  // If we have a PT_DYNAMIC header, we will either check the found dynamic
-  // section or take the dynamic table data directly from the header.
-  if (!DynamicPhdr)
-    return;
 
   if (DynamicPhdr->p_offset + DynamicPhdr->p_filesz >
       ObjF->getMemoryBufferRef().getBufferSize())
@@ -1377,6 +1374,7 @@ void ELFDumper<ELFT>::loadDynamicTable(c
   }
 
   StringRef Name = unwrapOrError(Obj->getSectionName(DynamicSec));
+
   if (DynamicSec->sh_addr + DynamicSec->sh_size >
           DynamicPhdr->p_vaddr + DynamicPhdr->p_memsz ||
       DynamicSec->sh_addr < DynamicPhdr->p_vaddr)
@@ -1388,6 +1386,8 @@ void ELFDumper<ELFT>::loadDynamicTable(c
     reportWarning("The SHT_DYNAMIC section '" + Name +
                   "' is not at the start of "
                   "PT_DYNAMIC segment");
+
+  parseDynamicTable();
 }
 
 template <typename ELFT>