[PATCH][gdb/testsuite] Fix gdb.cp/step-and-next-inline.exp with gcc-11

Tom de Vries
2021-07-21T08:31:52Z

Hi,

When running test-case gdb.cp/step-and-next-inline.exp with gcc-11, I run
into:
...
KPASS: gdb.cp/step-and-next-inline.exp: no_header: next step 1 \
(PRMS symtab/25507)
FAIL: gdb.cp/step-and-next-inline.exp: no_header: next step 2
KPASS: gdb.cp/step-and-next-inline.exp: no_header: next step 3 \
(PRMS symtab/25507)
...

[ Note that I get the same result with gcc-11 and target board
unix/gdb:debug_flags=-gdwarf-4, so this is not a dwarf 4 vs 5 issue. ]

With gcc-10, I have this trace:
...
64 get_alias_set (&xx);
get_alias_set (t=0x601038 <xx>) at step-and-next-inline.cc:51
51 if (t != NULL
40 if (t->x != i)
52 && TREE_TYPE (t).z != 1
43 return x;
53 && TREE_TYPE (t).z != 2
43 return x;
54 && TREE_TYPE (t).z != 3)
43 return x;
main () at step-and-next-inline.cc:65
65 return 0;
...
and with gcc-11, I have instead:
...
64 get_alias_set (&xx);
get_alias_set (t=0x601038 <xx>) at step-and-next-inline.cc:51
51 if (t != NULL
52 && TREE_TYPE (t).z != 1
43 return x;
53 && TREE_TYPE (t).z != 2
43 return x;
54 && TREE_TYPE (t).z != 3)
43 return x;
main () at step-and-next-inline.cc:65
65 return 0;
...
and with clang-10, I have instead:
...
64 get_alias_set (&xx);
get_alias_set (t=0x601034 <xx>) at step-and-next-inline.cc:51
51 if (t != NULL
52 && TREE_TYPE (t).z != 1
53 && TREE_TYPE (t).z != 2
54 && TREE_TYPE (t).z != 3)
51 if (t != NULL
57 }
main () at step-and-next-inline.cc:65
65 return 0;
...

The test-case tries to verify that we don't step into inlined function
tree_check (lines 40-43) (so, with the clang trace we get that right).

The test-case then tries to kfail the problems when using gcc, but this is
done in such a way that the testing still gets out of sync after a failure.
That is: the "next step 2" check that is supposed to match
"TREE_TYPE (t).z != 2" is actually matching "TREE_TYPE (t).z != 1":
...
(gdb) next^M
52 && TREE_TYPE (t).z != 1^M
(gdb) PASS: gdb.cp/step-and-next-inline.exp: no_header: next step 2
...

Fix this by issuing extra nexts to arrive at the required lines.

Tested on x86_64-linux, with gcc-8, gcc-9, gcc-10, gcc-11, clang-8, clang-10
and clang-12.

Any comments?

Thanks,
- Tom

[gdb/testsuite] Fix gdb.cp/step-and-next-inline.exp with gcc-11

gdb/testsuite/ChangeLog:

2021-07-20 Tom de Vries <tdevries@suse.de>

* gdb.cp/step-and-next-inline.cc (tree_check, get_alias_set, main):
Tag closing brace with comment.
* gdb.cp/step-and-next-inline.h: Update to keep identical with
step-and-next-inline.cc.
* gdb.cp/step-and-next-inline.exp: Issue extra next when required.

---
gdb/testsuite/gdb.cp/step-and-next-inline.cc | 6 +-
gdb/testsuite/gdb.cp/step-and-next-inline.exp | 89 ++++++++++++++++++++++++---
gdb/testsuite/gdb.cp/step-and-next-inline.h | 2 +-
3 files changed, 84 insertions(+), 13 deletions(-)

diff --git a/gdb/testsuite/gdb.cp/step-and-next-inline.cc b/gdb/testsuite/gdb.cp/step-and-next-inline.cc
index 6f0a7fbda9e..26b29d01777 100644
--- a/gdb/testsuite/gdb.cp/step-and-next-inline.cc
+++ b/gdb/testsuite/gdb.cp/step-and-next-inline.cc
@@ -41,7 +41,7 @@ tree_check (tree *t, int i)
abort();
tree *x = t;
return x;
-}
+} // tree-check

#endif /* USE_NEXT_INLINE_H */

@@ -54,7 +54,7 @@ get_alias_set (tree *t)
&& TREE_TYPE (t).z != 3)
return 0;
return 1;
-}
+} // get_alias_set

tree xx;

@@ -63,4 +63,4 @@ main()
{
get_alias_set (&xx);
return 0;
-}
+} // main
diff --git a/gdb/testsuite/gdb.cp/step-and-next-inline.exp b/gdb/testsuite/gdb.cp/step-and-next-inline.exp
index 85f7b8d5af1..13d801bb539 100644
--- a/gdb/testsuite/gdb.cp/step-and-next-inline.exp
+++ b/gdb/testsuite/gdb.cp/step-and-next-inline.exp
@@ -67,29 +67,100 @@ proc do_test { use_header } {
gdb_test "step" ".*" "step into get_alias_set"
gdb_test "bt" "\\s*\\#0\\s+get_alias_set\[^\r\]*${srcfile}:.*" \
"not in inline 1"
+
# It's possible that this first failure (when not using a header
# file) is GCC's fault, though the remaining failures would best
# be fixed by adding location views support (though it could be
# that some easier heuristic could be figured out). Still, it is
# not certain that the first failure wouldn't also be fixed by
# having location view support, so for now it is tagged as such.
- if {[test_compiler_info gcc*] && !$use_header} {
- setup_kfail "*-*-*" symtab/25507
+ set have_kfail [expr [test_compiler_info gcc*] && !$use_header]
+
+ set ok 1
+ gdb_test_multiple "next" "next step 1" {
+ -re -wrap "if \\(t->x != i\\)" {
+ set ok 0
+ send_gdb "next\n"
+ exp_continue
+ }
+ -re -wrap ".*TREE_TYPE.* != 1" {
+ if { $ok } {
+ pass $gdb_test_name
+ } else {
+ if { $have_kfail } {
+ setup_kfail "*-*-*" symtab/25507
+ }
+ fail $gdb_test_name
+ }
+ }
}
- gdb_test "next" ".*TREE_TYPE.*" "next step 1"
gdb_test "bt" "\\s*\\#0\\s+get_alias_set\[^\r\]*${srcfile}:.*" \
"not in inline 2"
- gdb_test "next" ".*TREE_TYPE.*" "next step 2"
+
+ set ok 1
+ gdb_test_multiple "next" "next step 2" {
+ -re -wrap "return x;" {
+ set ok 0
+ send_gdb "next\n"
+ exp_continue
+ }
+ -re -wrap ".*TREE_TYPE.* != 2" {
+ if { $ok } {
+ pass $gdb_test_name
+ } else {
+ if { $have_kfail } {
+ setup_kfail "*-*-*" symtab/25507
+ }
+ fail $gdb_test_name
+ }
+ }
+ }
gdb_test "bt" "\\s*\\#0\\s+get_alias_set\[^\r\]*${srcfile}:.*" \
"not in inline 3"
- if {[test_compiler_info gcc*] && !$use_header} {
- setup_kfail "*-*-*" symtab/25507
+
+ set ok 1
+ gdb_test_multiple "next" "next step 3" {
+ -re -wrap "return x;" {
+ set ok 0
+ send_gdb "next\n"
+ exp_continue
+ }
+ -re -wrap ".*TREE_TYPE.* != 3\\)" {
+ if { $ok } {
+ pass $gdb_test_name
+ } else {
+ if { $have_kfail } {
+ setup_kfail "*-*-*" symtab/25507
+ }
+ fail $gdb_test_name
+ }
+ }
}
- gdb_test "next" ".*TREE_TYPE.*" "next step 3"
gdb_test "bt" "\\s*\\#0\\s+get_alias_set\[^\r\]*${srcfile}:.*" \
"not in inline 4"
- if {!$use_header} { setup_kfail "*-*-*" symtab/25507 }
- gdb_test "next" "return 0.*" "next step 4"
+
+ set ok 1
+ gdb_test_multiple "next" "next step 4" {
+ -re -wrap "(if \\(t != NULL|\} // get_alias_set)" {
+ send_gdb "next\n"
+ exp_continue
+ }
+ -re -wrap "return x;" {
+ set ok 0
+ send_gdb "next\n"
+ exp_continue
+ }
+ -re -wrap "return 0.*" {
+ if { $ok } {
+ pass $gdb_test_name
+ } else {
+ if { $have_kfail } {
+ setup_kfail "*-*-*" symtab/25507
+ }
+ fail $gdb_test_name
+ }
+ }
+ }
gdb_test "bt" \
"\\s*\\#0\\s+(main|get_alias_set)\[^\r\]*${srcfile}:.*" \
"not in inline 5"
diff --git a/gdb/testsuite/gdb.cp/step-and-next-inline.h b/gdb/testsuite/gdb.cp/step-and-next-inline.h
index 8eb4b71d3cc..bf45d8a388c 100644
--- a/gdb/testsuite/gdb.cp/step-and-next-inline.h
+++ b/gdb/testsuite/gdb.cp/step-and-next-inline.h
@@ -35,4 +35,4 @@ tree_check (tree *t, int i)
abort();
tree *x = t;
return x;
-}
+} // tree_check