flip the default for -g (#1546)

When the -g flag was introduced, it defaulted to true, so that DWARF experiments needn't set it. Now that tests can set //MOC-FLAG, that is not necessary any more.

One exception is the hard setting of true when in linking mode, but this might be reconsidered in the future.

Author: ggreif

src/exes/mo_ld.ml

@@ -59,6 +59,7 @@ let () =
   if !lib_file = "" then usage_err "no library file specified";
   if !out_file = "" then usage_err "no output file specified";
 
+  Mo_config.Flags.debug_info := true; (* linking mode: preserve debug info *)
 
   let base = decode_file !base_file in
   let lib = decode_file !lib_file in

src/mo_config/flags.ml

@@ -10,7 +10,7 @@ let print_warnings = ref true
 let print_depth = ref 2
 let release_mode = ref false
 let compile_mode = ref ICMode
-let debug_info = ref true
+let debug_info = ref false
 let multi_value = ref false
 let await_lowering = ref true
 let async_lowering = ref true

src/wasm-exts/customModuleEncode.ml

@@ -650,8 +650,7 @@ let encode (em : extended_module) =
         section 2 (assoc_list (assoc_list string)) ns.locals_names  (ns.locals_names <> []) in
 
       custom_section "name" name_section_body ns
-        (!Mo_config.Flags.debug_info &&
-           (ns.module_ <> None || ns.function_names <> [] || ns.locals_names <> []))
+        (ns.module_ <> None || ns.function_names <> [] || ns.locals_names <> [])
 
     let uleb128 n = vu64 (Int64.of_int n)
     let sleb128 n = vs64 (Int64.of_int n)