[R] Re: R and gdb (still)

[Douglas Bates]

You are setting a breakpoint at an explicit line number

(gdb) b foo.c:21
Breakpoint 1 at 0x705c6004: file foo.c, line 21.

A safer way of setting the breakpoint is on the function name that the
R function "foo" calls through .C or .Call.  That way you are ensured
that the breakpoint will be encountered.  Line numbering within the
debugger can be peculiar and it may happen that the debugger never
gets to a point that it recognizes as being on line 21.