Converter bug fixes (#9700)

* Fixes #9698
* Fixes #9699

compiler/semcall.nim

@@ -138,6 +138,7 @@ proc effectProblem(f, a: PType; result: var string) =
 
 proc renderNotLValue(n: PNode): string =
   result = $n
+  let n = if n.kind == nkHiddenDeref: n[0] else: n
   if n.kind == nkHiddenCallConv and n.len > 1:
     result = $n[0] & "(" & result & ")"
   elif n.kind in {nkHiddenStdConv, nkHiddenSubConv} and n.len == 2:
@@ -394,6 +395,7 @@ proc resolveOverloads(c: PContext, n, orig: PNode,
         args])
 
 proc instGenericConvertersArg*(c: PContext, a: PNode, x: TCandidate) =
+  let a = if a.kind == nkHiddenDeref: a[0] else: a
   if a.kind == nkHiddenCallConv and a.sons[0].kind == nkSym:
     let s = a.sons[0].sym
     if s.ast != nil and s.ast[genericParamsPos].kind != nkEmpty:

compiler/semexprs.nim

@@ -640,6 +640,7 @@ proc analyseIfAddressTakenInCall(c: PContext, n: PNode) =
 
     return
   for i in countup(1, sonsLen(n) - 1):
+    let n = if n.kind == nkHiddenDeref: n[0] else: n
     if n.sons[i].kind == nkHiddenCallConv:
       # we need to recurse explicitly here as converters can create nested
       # calls and then they wouldn't be analysed otherwise

compiler/sigmatch.nim

@@ -13,7 +13,7 @@
 import
   intsets, ast, astalgo, semdata, types, msgs, renderer, lookups, semtypinst,
   magicsys, condsyms, idents, lexer, options, parampatterns, strutils, trees,
-  linter, lineinfos, modulegraphs
+  linter, lineinfos, lowerings, modulegraphs
 
 when (defined(booting) or defined(nimsuggest)) and not defined(leanCompiler):
   import docgen
@@ -1855,8 +1855,14 @@ proc userConvMatch(c: PContext, m: var TCandidate, f, a: PType,
       else:
         param = copyTree(arg)
       addSon(result, param)
+
+      if dest.kind in {tyVar, tyLent}:
+        dest.flags.incl tfVarIsPtr
+        result = newDeref(result)
+
       inc(m.convMatches)
-      m.genericConverter = srca == isGeneric or destIsGeneric
+      if m.genericConverter == false:
+        m.genericConverter = srca == isGeneric or destIsGeneric
       return result
 
 proc localConvMatch(c: PContext, m: var TCandidate, f, a: PType,