[lldb] Update the check for Linux or FreeBSD in SymbolFileDWARF::FindFunctions
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:
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).
Differential revision: https://reviews.llvm.org/D27380
llvm-svn: 288687
diff --git a/lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp b/lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp
index 406fa50..eb98315 100644
--- a/lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp
+++ b/lldb/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);