IssueTracker

I found there are line numbers in mapping file start from 0 such as this one:

com.google.gson.internal.bind.DateTypeAdapter -> v3.c:
    com.google.gson.TypeAdapterFactory FACTORY -> c
    java.text.DateFormat localFormat -> b
    java.text.DateFormat enUsFormat -> a
    10055:10059:java.util.Date read(com.google.gson.stream.JsonReader):55:59 -> a
    10055:10059:java.lang.Object read(com.google.gson.stream.JsonReader):41 -> a
    10100:10174:java.util.Date deserializeToDate(java.lang.String):0:74 -> a
    10100:10174:java.util.Date read(com.google.gson.stream.JsonReader):59 -> a
    10100:10174:java.lang.Object read(com.google.gson.stream.JsonReader):41 -> a
    41:41:void write(com.google.gson.stream.JsonWriter,java.lang.Object) -> b
    10000:10085:void write(com.google.gson.stream.JsonWriter,java.util.Date):0:85 -> b
    10000:10085:void write(com.google.gson.stream.JsonWriter,java.lang.Object):41 -> b

From this mapping info, it's obviously that 10100:10174:java.util.Date deserializeToDate(java.lang.String):0:74 -> a is NOT correct.

R8 version: 4.0.54

I did som dig in R8 source code, and found out that debug info is NOT correct when finalizing IR to dex cause its debug info events is like this:
DebugInfo (line 55) events: [
  DEFAULT 14 (dpc 0, dline 0)
  DEFAULT 135 (dpc 8, dline 1)
  DEFAULT 92 (dpc 5, dline 3)
  SET_POSITION_FRAME #0:deserializeToDate;59:read
  ADVANCE_LINE -59
  DEFAULT 74 (dpc 4, dline 0)
  ADVANCE_LINE 64
  DEFAULT 29 (dpc 1, dline 0)
  DEFAULT 168 (dpc 10, dline 4)
  DEFAULT 138 (dpc 8, dline 4)
  DEFAULT 211 (dpc 13, dline 2)
  END_SEQUENCE
]

And before output mapping, this method's debug info events is like this:
DebugInfo (line 41) events: [
  DEFAULT 14 (dpc 0, dline 0)
  SET_POSITION_FRAME #0:write;41:write
  ADVANCE_LINE -41
  DEFAULT 44 (dpc 2, dline 0)
  ADVANCE_LINE 80
  DEFAULT 59 (dpc 3, dline 0)
  DEFAULT 60 (dpc 3, dline 1)
  DEFAULT 46 (dpc 2, dline 2)
  DEFAULT 105 (dpc 6, dline 1)
  DEFAULT 60 (dpc 3, dline 1)
  END_SEQUENCE
]