Hi Sam,
On 16 Oct 2024, at 22:06, Sam James wrote:
> Simon Martin <si...@nasilyan.com> writes:
>
>> We ICE upon the following invalid code because we end up calling
>> finalize_nrv_r with a RETURN_EXPR with no operand.
>>
>> === cut here ===
>> struct X {
>> ~X();
>> };
>> X test(bool b) {
>> {
>> X x;
>> return x;
>> }
>> if (!(b)) return;
>> }
>> === cut here ===
>>
>> This patch fixes this by simply returning error_mark_node when
>> detecting
>> a void return in a function returning non-void.
>>
>> Successfully tested on x86_64-pc-linux-gnu.
>>
>> PR c++/117099
>>
>> gcc/cp/ChangeLog:
>>
>> * typeck.cc (check_return_expr): Return error_mark_node upon
>> void return for function returning non-void.
>>
>> gcc/testsuite/ChangeLog:
>>
>> * g++.dg/parse/crash77.C: New test.
>>
>> ---
>> gcc/cp/typeck.cc | 1 +
>> gcc/testsuite/g++.dg/parse/crash77.C | 14 ++++++++++++++
>> 2 files changed, 15 insertions(+)
>> create mode 100644 gcc/testsuite/g++.dg/parse/crash77.C
>>
>> diff --git a/gcc/cp/typeck.cc b/gcc/cp/typeck.cc
>> index 71d879abef1..22a6ec9a185 100644
>> --- a/gcc/cp/typeck.cc
>> +++ b/gcc/cp/typeck.cc
>> @@ -11238,6 +11238,7 @@ check_return_expr (tree retval, bool
>> *no_warning, bool *dangling)
>> RETURN_EXPR to avoid control reaches end of non-void function
>> warnings in tree-cfg.cc. */
>> *no_warning = true;
>> + return error_mark_node;
>> }
>> /* Check for a return statement with a value in a function that
>> isn't supposed to return a value. */
>> diff --git a/gcc/testsuite/g++.dg/parse/crash77.C
>> b/gcc/testsuite/g++.dg/parse/crash77.C
>> new file mode 100644
>> index 00000000000..d3f0ae6a877
>> --- /dev/null
>> +++ b/gcc/testsuite/g++.dg/parse/crash77.C
>> @@ -0,0 +1,14 @@
>> +// PR c++/117099
>> +// { dg-compile }
>
> dg-do compile
>
Aarg, of course, thanks for spotting this! Fixed in the attached
version.
>> +
>> +struct X {
>> + ~X();
>> +};
>> +
>> +X test(bool b) {
>> + {
>> + X x;
>> + return x;
>> + }
>> + if (!(b)) return; // { dg-error "return-statement with no value" }
>> +}
>> --
>> 2.44.0
>>
>
> BTW, the line-endings on this seem a bit odd. Did you use
> git-send-email?
I did use git-send-email indeed. What oddities do you see with line
endings?
cat -A over the patch file looks good.
Thanks, Simon
From 46fcb8cd0f89213b80f2815f6b7c2af064d7e86d Mon Sep 17 00:00:00 2001
From: Simon Martin <si...@nasilyan.com>
Date: Wed, 16 Oct 2024 15:47:12 +0200
Subject: [PATCH] c++: Fix crash during NRV optimization with invalid input
[PR117099]
We ICE upon the following invalid code because we end up calling
finalize_nrv_r with a RETURN_EXPR with no operand.
=== cut here ===
struct X {
~X();
};
X test(bool b) {
{
X x;
return x;
}
if (!(b)) return;
}
=== cut here ===
This patch fixes this by simply returning error_mark_node when detecting
a void return in a function returning non-void.
Successfully tested on x86_64-pc-linux-gnu.
PR c++/117099
gcc/cp/ChangeLog:
* typeck.cc (check_return_expr): Return error_mark_node upon
void return for function returning non-void.
gcc/testsuite/ChangeLog:
* g++.dg/parse/crash77.C: New test.
---
gcc/cp/typeck.cc | 1 +
gcc/testsuite/g++.dg/parse/crash77.C | 14 ++++++++++++++
2 files changed, 15 insertions(+)
create mode 100644 gcc/testsuite/g++.dg/parse/crash77.C
diff --git a/gcc/cp/typeck.cc b/gcc/cp/typeck.cc
index 71d879abef1..22a6ec9a185 100644
--- a/gcc/cp/typeck.cc
+++ b/gcc/cp/typeck.cc
@@ -11238,6 +11238,7 @@ check_return_expr (tree retval, bool *no_warning, bool
*dangling)
RETURN_EXPR to avoid control reaches end of non-void function
warnings in tree-cfg.cc. */
*no_warning = true;
+ return error_mark_node;
}
/* Check for a return statement with a value in a function that
isn't supposed to return a value. */
diff --git a/gcc/testsuite/g++.dg/parse/crash77.C
b/gcc/testsuite/g++.dg/parse/crash77.C
new file mode 100644
index 00000000000..912b997177c
--- /dev/null
+++ b/gcc/testsuite/g++.dg/parse/crash77.C
@@ -0,0 +1,14 @@
+// PR c++/117099
+// { dg-do compile }
+
+struct X {
+ ~X();
+};
+
+X test(bool b) {
+ {
+ X x;
+ return x;
+ }
+ if (!(b)) return; // { dg-error "return-statement with no value" }
+}
--
2.44.0
