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fix: stop emitting `.debug_pubnames` and `.debug_pubtypes` A continuation of #94181. Fixes #48762 MCP can be found in <https://github.com/rust-lang/compiler-team/issues/688>. `.debug_pubnames` and `.debug_pubtypes` are poorly designed and people seldom use them. However, they take a considerable portion of size in the final binary. This tells LLVM stop emitting those sections on DWARFv4 or lower. DWARFv5 use `.debug_names` which is more concise in size and performant for name lookup. Some other no-really-useful personal notes: <details><summary>Details</summary> <p> ## Pepole saying they are not useful * https://github.com/rust-lang/rust/issues/48762 * https://rust-lang.zulipchat.com/#narrow/stream/317568-t-compiler.2Fwg-debugging/topic/investigating.20debuginfo.20size/near/342713604 * `DwarfCompileUnit::hasDwarfPubSections()` —f633f325a1/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp (L1477-L1494)* clang default to no debug name table when no option provided —f633f325a1/clang/lib/Frontend/CompilerInvocation.cpp (L1819-L1824)* GCC explicitly says GDB doesn't use pub sections (`TARGET_WANT_DEBUG_PUB_SECTIONS` only be true on Darwin) —5d2a360f0a/gcc/target.def (L6985-L6990)and319b460545/gold/dwarf_reader.h (L424-L427)* Probably the only place that makes use of pub section in lldb —725115d7bb/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp (L2117-L2135)* "The -gsplit-dwarf option requires -ggnu-pubnames." —5d2a360f0a/gcc/opts.cc (L1205)* LLVM: Always emit `.debug_names` with dwarf 5 for Apple platforms — https://reviews.llvm.org/D118754 </p> </details>