FIXME: key change merge

[Roy . Rankin]

I commonly get the following warning

warning: FIXME: key change merge

Does this indicate a problem with the .ly file or that the code needs
to be fixed. If it is the former I humbly asked what I need to fix(I
have checked the manual), if the latter does this need to be fixed up
before 1.4?

Regards
Roy Rankin

\header {
title = "Grandola Vila Morena";
composer = "Words and Melody: Jose Afonso\\\\Choral Arrangment: Migule 
Heatwole, 1998";
tagline = "Transcription Roy Rankin 20/12/00";
}
t_lyric = \lyrics
{
        Em ca- da\_es-  "\'na\_um"  \"a- \`mi- \^go, em ca- da ros- "to\_i-" 
        gual- da- de. 
}
t_notes = \notes \relative c'
{
    \property Staff.instrument = "Tenor"
    \property Staff.instr = "T"
    \property Staff.midiInstrument = "trombone"

    \property Staff.TimeSignature \override #'style = #'C
    \property Voice.automaticMelismata = ##t
    \property Voice.DynamicLineSpanner \override #'direction = #1

        \key d \major; \time 4/4;
        \clef "G_8";
        \key g \major; 
        \time 2/4; 
        % 20
        r4^"2" g8. fis16 | 
        \time 4/4; g8. fis16 g8. a16 b4 ([) a8. () b32 () a32 ]|
        g2. c8. c16 | c2 r8. b16 c8. d16 |
        e4 ([) d8. () e32 () d32 ] c2    | \break
}

\score 
{
    <
        \addlyrics
        \context Staff="T"
        {
            \t_notes
        }
        \context Lyrics="T"
        <
                 {\t_lyric }
        >
    >
    \paper 
    {
        font_normal = 12.;
        \translator
        {
             \HaraKiriStaffContext
             \consists Bar_number_engraver; 
             noAutoBeaming = ##t;
        }
    }
}