[llvm] Non-functional change: declared a couple of local variables as const.

[dblaikie]

llvm/include/llvm/MC/MCContext.h

528 ↗

(On Diff #191769)

This doesn't immediately make sense to me - 'find' probably (I haven't double checked the type of MCDwarfLineTablesCUMap to confirm this, but find on most containers works this way) returns an iterator by value. Binding that to a reference is a bit surprising/confusing/unnecessary (& relies on reference lifetime extension - a rarely used/subtle feature)

So probably don't make this change.

llvm/lib/MC/MCAsmStreamer.cpp

1914

Seems reasonable

[tamur]

Reverted changes to llvm/MC/MCContext.h

[dblaikie]

Looks good - thanks!

llvm/lib/MC/MCAsmStreamer.cpp

 void MCAsmStreamer::FinishImpl() {
   // If we are generating dwarf for assembly source files dump out the sections.
   if (getContext().getGenDwarfForAssembly())
     MCGenDwarfInfo::Emit(this);
 
   // Emit the label for the line table, if requested - since the rest of the
   // line table will be defined by .loc/.file directives, and not emitted
   // directly, the label is the only work required here.
-  auto &Tables = getContext().getMCDwarfLineTables();
+  const auto &Tables = getContext().getMCDwarfLineTables();
   if (!Tables.empty()) {
     assert(Tables.size() == 1 && "asm output only supports one line table");
     if (auto *Label = Tables.begin()->second.getLabel()) {
       SwitchSection(getContext().getObjectFileInfo()->getDwarfLineSection());
       EmitLabel(Label);
     }
   }
 }