[R] Mysterious seg fault.

[Göran Broström]

Rolf,

have you tried to run R with a debugger, as in

$ R -d gdb

the gnu debugger?

G,

On 2018-08-11 23:12, Rolf Turner wrote:
> 
> I am getting a seg fault from a package that I am working on, and I am 
> totally flummoxed by it.  The fault presumably arises from dynamically
> loaded Fortran code, but I'm damned if I can see where the error lies.
> 
> In an effort to diagnose the problem I created a "non-package" version 
> of the code.  That is, I copied all the *.R files and *.f file into a
> new directory.  In that directory I created a *.so file using
> R CMD SHLIB.
> 
> In the R code I removed all the "PACKAGE=" lines from the calls to
> .Fortran() and put in appropriate dyn.load() calls.
> 
> I then started R in this new "clean" directory and sourced all of the
> *.R files.
> 
> I then issued the command that produces the seg fault when run under the 
> aegis of the package.  The command ran without a murmur of complaint.
> WTF?
> 
> Can anyone suggest a reason why a seg fault might arise when the code is 
> run in the context of a package, but not when it is run in "standalone 
> mode"?
> 
> I have checked and rechecked my init.c file --- which is the only thing 
> that I can think of that might create a difference --- and cannot find 
> any discrepancy between the declarations in the init.c file and the 
> Fortran code.
> 
> The package is a bit complicated, so giving more detail would be 
> cumbersome.  Also I have no idea what aspects of detail would be 
> relevant.  If anyone would like more info, feel free to ask.
> 
> I would really appreciate it if someone could give me some suggestions
> before I go *completely* mad!
> 
> cheers,
> 
> Rolf Turner
>