gdb.base/sigstep.exp failures

[Ulrich Weigand]

FAIL: gdb.base/sigstep.exp: step from handler; leave handler (timeout)
FAIL: gdb.base/sigstep.exp: stepi from handleri; leave signal trampoline
FAIL: gdb.base/sigstep.exp: next from handler; leave handler (timeout)
FAIL: gdb.base/sigstep.exp: nexti from handleri; leave signal trampoline
FAIL: gdb.base/sigstep.exp: step on breakpoint, to handler; performing step
FAIL: gdb.base/sigstep.exp: next on breakpoint, to handler; performing next
FAIL: gdb.base/sigstep.exp: continue on breakpoint, to handler; performing continue
FAIL: gdb.base/sigstep.exp: step on breakpoint, to handler entry; performing step
FAIL: gdb.base/sigstep.exp: next on breakpoint, to handler entry; performing next
FAIL: gdb.base/sigstep.exp: continue on breakpoint, to handler entry; performing continue

Further analysis required. Probably needs enhancements to signal framer unwinders.

[Yao Qi (yao-codesourcery)]

[CodeSourcery #7810]

[Yao Qi (yao-codesourcery)]

The first four failures are caused by a mistake when compute the next pc of instruction svc. Here is a patch to fix this,
diff --git a/gdb/arm-tdep.c b/gdb/arm-tdep.c
index 1ac8817..978bb72 100644
--- a/gdb/arm-tdep.c
+++ b/gdb/arm-tdep.c
@@ -3257,7 +3257,18 @@ arm_get_next_pc_raw (struct frame_info *frame, CORE_ADDR pc, int insert_bkpt)
        case 0xc:
        case 0xd:
        case 0xe: /* coproc ops */
+ break;
        case 0xf: /* SWI */
+ {
+ unsigned long svc_number = get_frame_register_unsigned (frame, 7);
+
+ if (svc_number == 119 || svc_number == 173)
+ {
+ if (get_frame_type (frame) == SIGTRAMP_FRAME)
+ {
+ nextpc = frame_unwind_caller_pc (frame);
+ }
+ }
          break;

        default:
--------------------------------------
After this patch is applied, first four failures goes away,

Running ../../../src/gdb/testsuite/gdb.base/sigstep.exp ...
FAIL: gdb.base/sigstep.exp: step on breakpoint, to handler; performing step
FAIL: gdb.base/sigstep.exp: next on breakpoint, to handler; performing next
FAIL: gdb.base/sigstep.exp: continue on breakpoint, to handler; performing continue
FAIL: gdb.base/sigstep.exp: step on breakpoint, to handler entry; performing step
FAIL: gdb.base/sigstep.exp: next on breakpoint, to handler entry; performing next
FAIL: gdb.base/sigstep.exp: continue on breakpoint, to handler entry; performing continue

                === gdb Summary ===

# of expected passes 113
# of unexpected failures 6
/home/yao/cvs/build/gdb/testsuite/../../gdb/gdb version 7.2.50.20100820-cvs -nw -nx

[Yao Qi (yao-codesourcery)]

Patch to fix the first four failures are sent to gdb-patches to review.
http://www.cygwin.com/ml/gdb-patches/2010-08/msg00440.html

[Yao Qi (yao-codesourcery)]

Patch in comment#3 was committed to gdb mainline and 7.2 branch.
http://www.cygwin.org/ml/gdb-cvs/2010-08/msg00191.html
http://www.cygwin.org/ml/gdb-cvs/2010-08/msg00190.html

[Ulrich Weigand (uweigand)]

I've opened bug #649121 to track the remaining problem, which seem to have a completely different cause.