[Lldb-commits] [PATCH] D27380: [lldb] Update the check for Linux or FreeBSD in SymbolFileDWARF::FindFunctions.

[Alexander Shaposhnikov via Phabricator via lldb-commits]

alexshap created this revision.
alexshap added reviewers: clayborg, spyffe.
alexshap added a subscriber: lldb-commits.
alexshap set the repository for this revision to rL LLVM.

This diff

1. Adds a comment to ObjectFileELF.cpp about the current

approach to determining the OS.

2. Replaces the check in SymbolFileDWARF.cpp with a more robust one.

Test plan:

1. Checked that the build is green.
2. Built (on Linux) a test binary linked to a c++ shared library

which contains just an implementation of a function TestFunction,
the library (the binary itself) doesn't contain ELF notes and EI_OSABI is set to System V.
Checked in lldb that now "p TestFunction()" works fine (and doesn't work without this patch).


Repository:
  rL LLVM

https://reviews.llvm.org/D27380

Files:
  source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp
  source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp


Index: source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
===================================================================
--- source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
+++ source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
@@ -2586,7 +2586,7 @@
       if (sc_list.GetSize() == original_size) {
         ArchSpec arch;
         if (!parent_decl_ctx && GetObjectFile()->GetArchitecture(arch) &&
-            (arch.GetTriple().isOSFreeBSD() || arch.GetTriple().isOSLinux() ||
+            (arch.GetTriple().isOSBinFormatELF() ||
              arch.GetMachine() == llvm::Triple::hexagon)) {
           SymbolContextList temp_sc_list;
           FindFunctions(name, m_function_basename_index, include_inlines,
Index: source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp
===================================================================
--- source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp
+++ source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp
@@ -1513,8 +1513,14 @@
     const uint32_t sub_type = subTypeFromElfHeader(header);
     arch_spec.SetArchitecture(eArchTypeELF, header.e_machine, sub_type,
                               header.e_ident[EI_OSABI]);
-    //
-    // Validate if it is ok to remove GetOsFromOSABI
+    
+    // Validate if it is ok to remove GetOsFromOSABI.
+    // Note, that now the OS is determined based on EI_OSABI flag and
+    // the info extracted from ELF notes (see RefineModuleDetailsFromNote).
+    // However in some cases that still might be not enough: for example
+    // a shared library might not have any notes at all
+    // and have EI_OSABI flag set to System V,
+    // as result the OS will be set to UnknownOS.
     GetOsFromOSABI(header.e_ident[EI_OSABI], ostype);
     spec_ostype = arch_spec.GetTriple().getOS();
     assert(spec_ostype == ostype);


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D27380.80161.patch
Type: text/x-patch
Size: 1805 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/lldb-commits/attachments/20161203/c5528c51/attachment-0001.bin>