[gdb/testsuite] Use maint ignore-probes in gdb.base/solib-corrupted.exp

Test-case gdb.base/solib-corrupted.exp only works for a glibc without probes
interface, otherwise we run into:
...
XFAIL: gdb.base/solib-corrupted.exp: info probes
UNTESTED: gdb.base/solib-corrupted.exp: GDB is using probes
...

Fix this by using maint ignore-probes to simulate the absence of the relevant
probes.

Also, it requires glibc debuginfo, and if not present, it produces an XFAIL:
...
XFAIL: gdb.base/solib-corrupted.exp: make solibs looping
UNTESTED: gdb.base/solib-corrupted.exp: no _r_debug symbol has been found
...
This is incorrect, because an XFAIL indicates a known problem in the
environment.  In this case, there is no problem: the environment is
functioning as expected when glibc debuginfo is not installed.

Fix this by using UNSUPPORTED instead, and make the message less cryptic:
...
UNSUPPORTED: gdb.base/solib-corrupted.exp: make solibs looping \
  (glibc debuginfo required)
...

Finally, with glibc debuginfo present, we run into:
...
(gdb) PASS: gdb.base/solib-corrupted.exp: make solibs looping
info sharedlibrary^M
warning: Corrupted shared library list: 0x7ffff7ffe750 != 0x0^M
From                To                  Syms Read   Shared Object Library^M
0x00007ffff7dd4170  0x00007ffff7df4090  Yes         /lib64/ld-linux-x86-64.so.2^M
(gdb) FAIL: gdb.base/solib-corrupted.exp: corrupted list \
  (shared library list corrupted)
...
due to commit 44288716537 ("gdb, testsuite: extend gdb_test_multiple checks").

Fix this by rewriting into gdb_test_multiple and using -early.

Tested on x86_64-linux, with and without glibc debuginfo installed.

1 files changed, 14 insertions, 12 deletions

diff --git a/gdb/testsuite/gdb.base/solib-corrupted.exp b/gdb/testsuite/gdb.base/solib-corrupted.exp
index e778711..24ee2d4 100644
--- a/gdb/testsuite/gdb.base/solib-corrupted.exp
+++ b/gdb/testsuite/gdb.base/solib-corrupted.exp
@@ -26,14 +26,14 @@ if { [prepare_for_testing "failed to prepare" ${testfile} ${srcfile}] } {
     return -1
 }
 
+# With probes interface GDB no longer scans the inferior library list so its
+# corruption cannot be tested.  Disable the probes interface.
+gdb_test "maint ignore-probes rtld"
+
 if ![runto_main] {
     return
 }
 
-# With probes interface GDB no longer scans the inferior library list so its
-# corruption cannot be tested.  There is no way to disable the probes
-# interface.
-
 set probes { init_start init_complete map_start reloc_complete unmap_start
 	     unmap_complete }
 set test "info probes"
@@ -51,11 +51,7 @@ gdb_test_multiple $test $test {
     -re "^$gdb_prompt $" {
     }
 }
-if { [llength $probes] == 0 } {
-    xfail $test
-    untested "GDB is using probes"
-    return
-}
+gdb_assert {[llength $probes] == 6} "no probes found"
 
 gdb_test "info sharedlibrary" "From * To .*" "normal list"
 
@@ -75,12 +71,18 @@ gdb_test_multiple "p/x _r_debug->r_map->l_next = _r_debug->r_map" $test {
     -re "$no_glibc_debuginfo_re\r\n$gdb_prompt $" {
 	# glibc debug info is not available and it is too difficult to find and
 	# parse it from this testcase without the gdb supporting functions.
-	xfail $test
-	untested "no _r_debug symbol has been found"
+	unsupported "$gdb_test_name (glibc debuginfo required)"
 	return
     }
     -re " = 0x\[0-9a-f\]+\r\n$gdb_prompt $" {
 	pass $test
     }
 }
-gdb_test "info sharedlibrary" "warning: Corrupted shared library list: .*" "corrupted list"
+
+# Use -early to prevent the default handling of the warning in gdb_test_multiple
+# from triggering.
+gdb_test_multiple "info sharedlibrary" "corrupted list" {
+    -early -re -wrap "warning: Corrupted shared library list: .*" {
+	pass $gdb_test_name
+    }
+}