* Set pi_uses_exceptions flag when creating/firstpassing ttryexceptnode or ttryfinallynode, not when parsing try statements. It ensures that procedures with exception handling nodes created by compiler (constructors in the first place, but also for..in loops with TObject iterators, etc.) are handled the same way as ones containing exception nodes from user code.

* Modified code generation for constructors so they don't always use pi_needs_implicit_finally. It used to prevent stackframe optimization while not preventing regvar optimization ( tabstractvarsym.is_regvar() checks for pi_uses_exceptions but not for pi_needs_implicit_finally, and constructors were not getting pi_uses_exceptions), resulting in strange code using both exceptions and regvars.
Once setting of pi_uses_exception is fixed, the implicit finally frame can be omitted unless managed temps or local vars are actually present.

git-svn-id: trunk@19668 -

compiler/nflw.pas

@@ -1985,6 +1985,7 @@ implementation
       begin
          result:=nil;
          include(current_procinfo.flags,pi_do_call);
+         include(current_procinfo.flags,pi_uses_exceptions);
          expectloc:=LOC_VOID;
          firstpass(left);
          { on statements }
@@ -2003,6 +2004,7 @@ implementation
     constructor ttryfinallynode.create(l,r:tnode);
       begin
         inherited create(tryfinallyn,l,r,nil,nil);
+        include(current_procinfo.flags,pi_uses_exceptions);
         implicitframe:=false;
       end;
 

compiler/pstatmnt.pas

@@ -821,8 +821,6 @@ implementation
          unit_found:boolean;
          oldcurrent_exceptblock: integer;
       begin
-         include(current_procinfo.flags,pi_uses_exceptions);
-
          p_default:=nil;
          p_specific:=nil;
 

compiler/psub.pas

@@ -303,7 +303,6 @@ implementation
               begin
                 if is_class(current_structdef) then
                   begin
-                    include(current_procinfo.flags,pi_needs_implicit_finally);
                     srsym:=search_struct_member(current_structdef,'NEWINSTANCE');
                     if assigned(srsym) and
                        (srsym.typ=procsym) then
@@ -718,7 +717,13 @@ implementation
           end
         else
           begin
-            maybe_add_constructor_wrapper(code,false);
+            { Constructors need the destroy-on-exception code even if they don't
+              use managed variables/temps. }
+            if (cs_implicit_exceptions in current_settings.moduleswitches) and
+               (is_class(procdef.struct) and (procdef.proctypeoption=potype_constructor)) then
+              maybe_add_constructor_wrapper(code,true)
+            else
+              maybe_add_constructor_wrapper(code,false);
             addstatement(newstatement,loadpara_asmnode);
             addstatement(newstatement,stackcheck_asmnode);
             addstatement(newstatement,entry_asmnode);