[lldb] Silence signed <-> unsigned integer comparison warning

[omtcyfz]

Summary

num_args is unsigned integer, declared as below:

uint32_t num_args = arg_enum->getChildCount();

Comparison with the signed arg_idx produces a warning when compiled with -Wsign-compare flag, this patch addresses this simple issue without affecting any functionality.

[asmith]

Thanks for fixing that!

[davide]

LGTM. unsigned is probably fine as well. Do you need somebody to commit this on your behalf?

[omtcyfz]

@asmith Thanks!

@davide Thanks for the input!
I'll be able to do land it since I have commit access, thanks!

lldb/trunk/source/Plugins/SymbolFile/PDB/PDBASTParser.cpp

if (auto udt = llvm::dyn_cast<PDBSymbolTypeUDT>(&type)) {
     auto arg_enum = func_sig->getArguments();
     uint32_t num_args = arg_enum->getChildCount();
     std::vector<CompilerType> arg_list;
 
     bool is_variadic = func_sig->isCVarArgs();
     // Drop last variadic argument.
     if (is_variadic)
       --num_args;
-    for (int arg_idx = 0; arg_idx < num_args; arg_idx++) {
+    for (uint32_t arg_idx = 0; arg_idx < num_args; arg_idx++) {
       auto arg = arg_enum->getChildAtIndex(arg_idx);
       if (!arg)
         break;
       lldb_private::Type *arg_type =
           m_ast.GetSymbolFile()->ResolveTypeUID(arg->getSymIndexId());
       // If there's some error looking up one of the dependent types of this
       // function signature, bail.
       if (!arg_type)