Re: parameter type is incorrectly reported by typeof()

[Andrew J. Schorr]

Oops, forgot the debug printf patch. Now attached.

On Tue, Nov 16, 2021 at 11:20:43AM -0500, Andrew J. Schorr wrote:
> Hi,
> 
> On Tue, Nov 16, 2021 at 01:38:22AM -0700, arnold@skeeve.com wrote:
> > The first 'untyped' is from the BEGIN and is correct. The second
> > one is also correct.  The third one is what you're asking about.
> 
> Yes.
> 
> > I think this is because `x' in the function comes from Node_param_list,
> > and when a value is fetched, it gets the null string.  Maybe the
> > type here should also be turned into unassigned.  It's very subtle
> > though and needs looking at in a debugger.
> > 
> > If I have some time I'll look at it.  Or feel free to beat me to it.
> 
> Simpler version:
> 
> bash-4.2$ cat /tmp/test1.awk
> function f(x) {
>    #print typeof(x)
>    y = x
>    print typeof(x)
> }
> 
> BEGIN {
>    #print typeof(x)
>    f(x)
> }
> 
> It prints "untyped", and from debugging, I see that the node
> type is 11 (Node_array_ref). That strikes me as odd.
> 
> bash-4.2$ ./gawk -D -f /tmp/test1.awk
> gawk> dump
> 
>         # BEGIN
> 
> [     7:0x12d9a48] Op_rule             : [in_rule = BEGIN] [source_file = 
> /tmp/test1.awk]
> [     9:0x12d72b0] Op_push_param       : x
> [     9:0x12d8558] Op_func_call        : [func_name = f] [arg_count = 1]
> [      :0x12d7378] Op_pop              : 
> [      :0x12d7148] Op_no_op            : 
> [      :0x12d71e8] Op_atexit           : 
> [      :0x12d73a0] Op_stop             : 
> [      :0x12d7198] Op_no_op            : 
> [      :0x12d71c0] Op_after_beginfile  : 
> [      :0x12d7170] Op_no_op            : 
> [      :0x12d7418] Op_after_endfile    : 
> 
>         # Function: f (x)
> 
> [     1:0x12d99a8] Op_func             : [param_cnt = 1] [source_file = 
> /tmp/test1.awk]
> [     3:0x12d7288] Op_push             : x
> [     3:0x12d7238] Op_store_var        : y
> [     4:0x12d72d8] Op_push_arg_untyped : x
> [     4:0x12d7260] Op_builtin          : typeof [arg_count = 1]
> [     4:0x12d7210] Op_K_print          : [expr_count = 1] [redir_type = ""]
> [      :0x12d7300] Op_push_i           : Nnull_string 
> [MALLOC|STRING|STRCUR|NUMCUR|NUMBER]
> [      :0x12d7328] Op_K_return         : 
> 
> The Op_store_var code in interpret.h assigns the results of
> POP_SCALAR to y, but that's somehow a different NODE than what is
> passed to do_typeof.
> 
> I did just enough debugging to get myself confused. With the attached
> patch containing debugging printfs, one sees:
> 
> bash-4.2$ ./gawk -f /tmp/test1.awk 
> debug: popped scalar 0x1799140 with type 1 [Node_val] flags 31 
> [MALLOC|STRING|STRCUR|NUMCUR|NUMBER]
> debug: typeof(0x17b0200) with type 11 [Node_array_ref] flags 0 []
> untyped
> 
> Whereas for this script:
> 
> bash-4.2$ cat /tmp/test.awk 
> BEGIN {
> #   print typeof(x)
>    y = x
>    print typeof(x)
> }
> 
> One sees:
> 
> bash-4.2$ ./gawk -f /tmp/test.awk 
> debug: popped scalar 0x9ba140 with type 1 [Node_val] flags 31 
> [MALLOC|STRING|STRCUR|NUMCUR|NUMBER]
> debug: typeof(0x9ba140) with type 1 [Node_val] flags 31 
> [MALLOC|STRING|STRCUR|NUMCUR|NUMBER]
> unassigned
> 
> Yet the logic is basically the same:
> [     1:0x259a9c8] Op_rule             : [in_rule = BEGIN] [source_file = 
> /tmp/test.awk]
> [     3:0x25982a8] Op_push             : x
> [     3:0x2598230] Op_store_var        : y
> [     4:0x25982f8] Op_push_arg_untyped : x
> [     4:0x2598280] Op_builtin          : typeof [arg_count = 1]
> [     4:0x2598258] Op_K_print          : [expr_count = 1] [redir_type = ""]
> [      :0x2598168] Op_no_op            : 
> [      :0x2598208] Op_atexit           : 
> [      :0x2598320] Op_stop             : 
> [      :0x25981b8] Op_no_op            : 
> [      :0x25981e0] Op_after_beginfile  : 
> [      :0x2598190] Op_no_op            : 
> [      :0x2598398] Op_after_endfile    : 
> 
> Regards,
> Andy

debug.patch
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