[Lldb-commits] [PATCH] D93438: ObjectFileELF: Test whether reloc_header is non-null instead of asserting.

[Peter Collingbourne via Phabricator via lldb-commits]

pcc created this revision.
pcc added a reviewer: labath.
Herald added a subscriber: emaste.
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It is possible for the GetSectionHeaderByIndex lookup to fail because
the previous FindSectionContainingFileAddress lookup found a segment
instead of a section. This is possible if the binary does not have
a PLT (which means that lld will in some circumstances set DT_JMPREL
to 0, which is typically an address that is part of the ELF headers
and not in a section) and may also be possible if the section headers
have been stripped. To handle this possibility, replace the assert
with an if.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D93438

Files:
  lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp


Index: lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp
===================================================================
--- lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp
+++ lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp
@@ -2758,14 +2758,14 @@
         user_id_t reloc_id = reloc_section->GetID();
         const ELFSectionHeaderInfo *reloc_header =
             GetSectionHeaderByIndex(reloc_id);
-        assert(reloc_header);
+        if (reloc_header) {
+          if (m_symtab_up == nullptr)
+            m_symtab_up =
+                std::make_unique<Symtab>(reloc_section->GetObjectFile());
 
-        if (m_symtab_up == nullptr)
-          m_symtab_up =
-              std::make_unique<Symtab>(reloc_section->GetObjectFile());
-
-        ParseTrampolineSymbols(m_symtab_up.get(), symbol_id, reloc_header,
-                               reloc_id);
+          ParseTrampolineSymbols(m_symtab_up.get(), symbol_id, reloc_header,
+                                 reloc_id);
+        }
       }
     }
 


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