Re: [PATCH] Print nonexisting/optimized out static fields gracefully.

[Doug Evans <dje@google.com>]

Pedro Alves writes:
 > With:
 > 
 >  struct static_struct { static int aaa; };
 >  struct static_struct sss;
 >  int main () { return 0; }
 > 
 > We get:
 > 
 >  (gdb) p sss
 >  $1 = {static aaa = <optimized out>}
 >  (gdb) p sss.aaa
 >  field aaa is nonexistent or has been optimized out
 > 
 > Note that the "field aaa ..." message is an error being thrown.
 > 
 > GDB is graceful everywhere else when printing optimized out values.
 > IOW it usually prints an <optimized out> value and puts that in the
 > value history.  I see no reason for here to be different, more so that
 > when the print the whole "containing" object (well, it's a static
 > field, so it's not really a container), we already print <optimized
 > out>.
 > 
 > After the patch:
 > 
 >  (gdb) p sss
 >  $1 = {static aaa = <optimized out>}
 >  (gdb) p sss.aaa
 >  field aaa is nonexistent or has been optimized out
 >  (gdb) p sss.aaa
 >  $2 = <optimized out>
 > 
 > The value_entirely_optimized_out checks are there to preserve
 > behavior.  Without those, if the static field is a struct/union, GDB
 > would go and print its fields one by one (and print <optimized out>
 > for each).
 > 
 > Tested on x86_64 Fedora 17.
 > 
 > gdb/
 > 2013-10-10  Pedro Alves  <palves@redhat.com>
 > 
 > 	* cp-valprint.c (cp_print_value_fields): No longer handle a NULL
 > 	static field value.
 > 	(cp_print_static_field): If the value is entirely optimized out,
 > 	print <optimized out> here.
 > 	* jv-valprint.c (java_print_value_fields): No longer handle a NULL
 > 	static field value.
 > 	* p-valprint.c (pascal_object_print_static_field): If the value is
 > 	entirely optimized out, print <optimized out> here.
 > 	* valops.c (do_search_struct_field)
 > 	(value_struct_elt_for_reference): No longer handle a NULL static
 > 	field value.
 > 	* value.c (value_static_field): Return an optimized out value
 > 	instead of NULL.
 > 
 > gdb/testsuite/
 > 2013-10-10  Pedro Alves  <palves@redhat.com>
 > 
 > 	* gdb.cp/m-static.exp: Adjust expected output of printing a
 > 	nonexistent or optimized out static field.  Also test printing the
 > 	the "container" object.

"works for me"
[modulo nit noticed by Yao]