[lldb] Improve identification of Linux core dumps. Fix for bug #30485.

[rnchamberlain]

Summary

ObjectFileELF::RefineModuleDetailsFromNote() identifies Linux core dumps by searching for
library paths starting with /lib/x86_64-linux-gnu or /lib/i386-linux-gnu. This change widens the
test to allow for linux installations which have addition directories in the path.

[rnchamberlain]

More information, including readelf output from the dump, in the bugzilla here: https://llvm.org/bugs/show_bug.cgi?id=30485

[hhellyer]

The change seems unlikely to pick up many false positives and core dumps from the type of system described in the bug are only going to get more common.

[clayborg]

Use "llvm::StringRef::contains". See inline comment.

source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp

1408–1409

I believe Zach Turner added a "contains" function to StringRef which we should use here:

if (path.contains("/lib/x86_64-linux-gnu") || path.contains("/lib/i386-linux-gnu")) {

[rnchamberlain]

Updating as suggested to use StringRef.contains()

[rnchamberlain]

Thanks, that's nicer. I did have a look for a 'contains()' method, but it has not made it into the docs yet.
http://llvm.org/docs/doxygen/html/classllvm_1_1StringRef.html

source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp

else if ((note.n_type == LLDB_NT_GNU_ABI_TAG) &&
           if (cstr == nullptr) {
             error.SetErrorStringWithFormat("ObjectFileELF::%s trying to read "
                                            "at an offset after the end "
                                            "(GetCStr returned nullptr)",
                                            __FUNCTION__);
             return error;
           }
           llvm::StringRef path(cstr);
-          if (path.startswith("/lib/x86_64-linux-gnu") ||
-              path.startswith("/lib/i386-linux-gnu")) {
+          if (path.contains("/lib/x86_64-linux-gnu") || path.contains("/lib/i386-linux-gnu")) {
             arch_spec.GetTriple().setOS(llvm::Triple::OSType::Linux);
             break;
           }
         }
       }
     }
 
     // Calculate the offset of the next note just in case "offset" has been used
     // to poke at the contents of the note data