gdb/

	Fix empty DWARF expressions DATA vs. SIZE conditionals.
	* dwarf2loc.c (dwarf2_find_location_expression): Clear *LOCEXPR_LENGTH.
	(dwarf_expr_frame_base_1): Indicate unavailability via zero *LENGTH.
	(locexpr_tracepoint_var_ref): Check only zero SIZE, not zero DATA.
	(loclist_read_variable, loclist_tracepoint_var_ref): Do not check for
	zero DATA.
	* dwarf2loc.h (struct dwarf2_locexpr_baton): Comment DATA vs. SIZE
	validity.
	* dwarf2read.c (struct dwarf_block): Comment DATA validity.
	(dwarf2_fetch_die_location_block, dwarf2_symbol_mark_computed): Do not
	clear DATA on zero SIZE.

gdb/testsuite/
	Fix empty DWARF expressions DATA vs. SIZE conditionals.
	* gdb.dwarf2/dw2-op-call.S (arraycallnoloc, arraynoloc): New DIEs.
	(loclist): New.
	(4): New abbrev.
	* gdb.dwarf2/dw2-op-call.exp: Remove variable srcfile and executable.
	Use prepare_for_testing, remove clean_restart.
	(p arraynoloc, p arraycallnoloc): New tests.

1 files changed, 8 insertions, 6 deletions

diff --git a/gdb/testsuite/gdb.dwarf2/dw2-op-call.exp b/gdb/testsuite/gdb.dwarf2/dw2-op-call.exp
index 3319133..416eef4 100644
--- a/gdb/testsuite/gdb.dwarf2/dw2-op-call.exp
+++ b/gdb/testsuite/gdb.dwarf2/dw2-op-call.exp
@@ -22,18 +22,20 @@ if {![dwarf2_support]} {
 }
 
 set testfile "dw2-op-call"
-set srcfile ${testfile}.S
-set executable ${testfile}.x
-
-if  { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${objdir}/${subdir}/${executable}" object {nodebug}] != "" } {
+if { [prepare_for_testing ${testfile}.exp ${testfile} [list ${testfile}.S main.c] {nodebug}] } {
     return -1
 }
 
-clean_restart $executable
-
 # Additional test to verify the referenced CU is not aged out.
 gdb_test_no_output "maintenance set dwarf2 max-cache-age 0"
 
 gdb_test "p array1" " = 1"
 gdb_test "p array2" " = 2" "array2 using DW_OP_call2"
 gdb_test "p array3" " = 3" "array3 using DW_OP_call4"
+
+# Location lists need PC.
+if ![runto_main] {
+    return -1
+}
+gdb_test "p arraynoloc" " = <optimized out>"
+gdb_test "p arraycallnoloc" {Asked for position 0 of stack, stack only has 0 elements on it\.}