The testcase has failed since r9-5035, because obj_type_ref_class
tries to look up an ODR type when no ODR type information is
available. (The information was available earlier in the
compilation, but was freed during pass_ipa_free_lang_data.)
We then crash dereferencing the null get_odr_type result.
The test passes with -O2. However, it fails again if -fdump-tree-all
is used, since obj_type_ref_class is called indirectly from the
dump routines.
Other code seems to create ODR type entries on the fly by passing
"true" as the insert parameter. But since obj_type_ref_class is
used by dump routines, I guess it should have no side-effects and
should simply punt in this case.
Tested on aarch64-linux-gnu and x86_64-linux-gnu. OK for master
and branches?
Richard
2020-05-14 Richard Sandiford <richard.sandif...@arm.com>
gcc/
PR middle-end/95114
* ipa-devirt.c (obj_type_ref_class): Cope with a null return
from get_odr_type.
gcc/testsuite/
PR middle-end/95114
* g++.target/aarch64/pr95114.C: New test.
---
gcc/ipa-devirt.c | 4 ++--
gcc/testsuite/g++.target/aarch64/pr95114.C | 3 +++
2 files changed, 5 insertions(+), 2 deletions(-)
create mode 100644 gcc/testsuite/g++.target/aarch64/pr95114.C
diff --git a/gcc/ipa-devirt.c b/gcc/ipa-devirt.c
index bd9f3441773..ac19eb75596 100644
--- a/gcc/ipa-devirt.c
+++ b/gcc/ipa-devirt.c
@@ -1911,8 +1911,8 @@ obj_type_ref_class (const_tree ref)
tree ret = TREE_TYPE (ref);
if (!in_lto_p && !TYPE_STRUCTURAL_EQUALITY_P (ret))
ret = TYPE_CANONICAL (ret);
- else
- ret = get_odr_type (ret)->type;
+ else if (odr_type ot = get_odr_type (ret))
+ ret = ot->type;
return ret;
}
diff --git a/gcc/testsuite/g++.target/aarch64/pr95114.C
b/gcc/testsuite/g++.target/aarch64/pr95114.C
new file mode 100644
index 00000000000..1689159e47c
--- /dev/null
+++ b/gcc/testsuite/g++.target/aarch64/pr95114.C
@@ -0,0 +1,3 @@
+template<typename T> struct foo { virtual void f() = 0; };
+extern foo<__Int8x8_t> &x;
+void f() { x.f(); }
