Get longjmp target check in breakpoint.c - is it necessary?

[Tiago Stürmer Daitx]

We have in gdb/breakpoint.c the following condition checking:

 3222       if (!gdbarch_get_longjmp_target_p (gdbarch))¬
 3223 »       continue;¬

Which is forcing me to implement an (unnecessary?) arch specific
get_longjmp_target while having a longjmp user probe in glibc should be
enough. Removing that if/continue statement showed no regressions - it
actually fixed 3 longjmp failures (assuming proper support in glibc for
a longjmp probe is in place). 

I would be glad to hear your thoughts on any possible side effects of
removing that statement.

$ diff -u gdb/testsuite/gdb.sum
gdb/testsuite/gdb-no-get-longjmp-target-check.sum

[snip]
-FAIL: gdb.base/longjmp.exp: next over longjmp(1)
+PASS: gdb.base/longjmp.exp: next over longjmp(1)
+PASS: gdb.base/longjmp.exp: next into else block (1)
+PASS: gdb.base/longjmp.exp: next into safety net (1)
 PASS: gdb.base/longjmp.exp: breakpoint at pattern 2 start
 PASS: gdb.base/longjmp.exp: continue to breakpoint at pattern 2 start
 PASS: gdb.base/longjmp.exp: breakpoint at miss_step_2
 PASS: gdb.base/longjmp.exp: next over setjmp (2)
-FAIL: gdb.base/longjmp.exp: next over call_longjmp (2)
+PASS: gdb.base/longjmp.exp: next over call_longjmp (2)
+PASS: gdb.base/longjmp.exp: next into else block (2)
+PASS: gdb.base/longjmp.exp: next into safety net (2)
[snip]
-XFAIL: gdb.base/stale-infcall.exp: test system longjmp tracking support
-UNTESTED: gdb.base/stale-infcall.exp: System lacks support for tracking
longjmps
+PASS: gdb.base/stale-infcall.exp: test system longjmp tracking support
+PASS: gdb.base/stale-infcall.exp: delete $test_fail_bpnum
+PASS: gdb.base/stale-infcall.exp: continue to breakpoint: break-run1
+PASS: gdb.base/stale-infcall.exp: print infcall ()
+PASS: gdb.base/stale-infcall.exp: stack corrupted
+PASS: gdb.base/stale-infcall.exp: bt
+PASS: gdb.base/stale-infcall.exp: maintenance print dummy-frames
+PASS: gdb.base/stale-infcall.exp: maintenance info breakpoints


Everything was tested on both PPC and PPC64. The glibc user probes have
been implemented but are not yet upstream.

Cheers!
-tiago

-- 
Tiago Stürmer Daitx
tdaitx@linux.vnet.ibm.com
IBM - Linux Technology Center