We are comparing enum values (in wide_int) to check ODR violation.
However, if we compare two wide_int values with different precision,
we'll trigger an assert, leading to ICE. With enum-base introduced
in C++11, it's easy to sink into this situation.
To fix the issue, we need to explicitly check this kind of mismatch,
and emit a proper warning message if there is such one.
Bootstrapped & regtested on x86_64-linux-gnu. Ok for trunk?
gcc/
PR ipa/101396
* ipa-devirt.c (ipa_odr_read_section): Compare the precision of
enum values, and emit a warning if they mismatch.
gcc/testsuite/
PR ipa/101396
* g++.dg/lto/pr101396_0.C: New test.
* g++.dg/lto/pr101396_1.C: New test.
---
gcc/ipa-devirt.c | 9 +++++++++
gcc/testsuite/g++.dg/lto/pr101396_0.C | 12 ++++++++++++
gcc/testsuite/g++.dg/lto/pr101396_1.C | 10 ++++++++++
3 files changed, 31 insertions(+)
create mode 100644 gcc/testsuite/g++.dg/lto/pr101396_0.C
create mode 100644 gcc/testsuite/g++.dg/lto/pr101396_1.C
diff --git a/gcc/ipa-devirt.c b/gcc/ipa-devirt.c
index 8cd1100aba9..8deec75b2df 100644
--- a/gcc/ipa-devirt.c
+++ b/gcc/ipa-devirt.c
@@ -4193,6 +4193,8 @@ ipa_odr_read_section (struct lto_file_decl_data
*file_data, const char *data,
if (do_warning != -1 || j >= this_enum.vals.length ())
continue;
if (strcmp (id, this_enum.vals[j].name)
+ || (val.get_precision() !=
+ this_enum.vals[j].val.get_precision())
|| val != this_enum.vals[j].val)
{
warn_name = xstrdup (id);
@@ -4260,6 +4262,13 @@ ipa_odr_read_section (struct lto_file_decl_data
*file_data, const char *data,
"name %qs differs from name %qs defined"
" in another translation unit",
this_enum.vals[j].name, warn_name);
+ else if (this_enum.vals[j].val.get_precision() !=
+ warn_value.get_precision())
+ inform (this_enum.vals[j].locus,
+ "name %qs is defined as %u-bit while another "
+ "translation unit defines it as %u-bit",
+ warn_name, this_enum.vals[j].val.get_precision(),
+ warn_value.get_precision());
/* FIXME: In case there is easy way to print wide_ints,
perhaps we could do it here instead of overflow check. */
else if (wi::fits_shwi_p (this_enum.vals[j].val)
diff --git a/gcc/testsuite/g++.dg/lto/pr101396_0.C
b/gcc/testsuite/g++.dg/lto/pr101396_0.C
new file mode 100644
index 00000000000..b7a2947a880
--- /dev/null
+++ b/gcc/testsuite/g++.dg/lto/pr101396_0.C
@@ -0,0 +1,12 @@
+/* { dg-lto-do link } */
+
+enum A : __UINT32_TYPE__ { // { dg-lto-warning "6: type 'A' violates the
C\\+\\+ One Definition Rule" }
+ a, // { dg-lto-note "3: name 'a' is defined as 32-bit while another
translation unit defines it as 64-bit" }
+ b,
+ c
+};
+
+int main()
+{
+ return (int) A::a;
+}
diff --git a/gcc/testsuite/g++.dg/lto/pr101396_1.C
b/gcc/testsuite/g++.dg/lto/pr101396_1.C
new file mode 100644
index 00000000000..a6d032d694d
--- /dev/null
+++ b/gcc/testsuite/g++.dg/lto/pr101396_1.C
@@ -0,0 +1,10 @@
+enum A : __UINT64_TYPE__ { // { dg-lto-note "6: an enum with different value
name is defined in another translation unit" }
+ a, // { dg-lto-note "3: mismatching definition" }
+ b,
+ c
+};
+
+int f(enum A x)
+{
+ return (int) x;
+}
--
2.32.0
