Slurs into chords

[Jonathan Danner]

Hello,

Im trying to make a slur, or even possibly a gliss into a chord and can’t quite 
get it right without getting a warning message. Can anyone provide a way I can 
do either of these?

My examples attached


\version "2.20.0"

\header {
  title = ""
}

global = {
  \time 4/4
  \key c \major
  \tempo 4=100
}

chordNames = \chordmode {
  \global
  c1
  
}

melody = \relative c'' {
  \global
 r8 a\f c a c4 e8 e~|e d16 (c) a4~a4 r|b8 b4. b4 c8 \once\override 
TextScript.X-offset = #-2  \once\override TextScript.Y-offset = #-2 \once 
\override Glissando.style = #'dashed-line   \slurDashed (d_~^\markup \teeny 
\rotate #45 {*gliss*}<<d4.\parenthesize d'2\bendAfter # 0 ^\markup 
\center-column \tiny {*optional*})>>
 r8 r2 
}

words = \lyricmode {
  
  
}

\score {
  <<


    \new Staff { \melody }

  >>
  \layout { }
  \midi { }
}