c++: fix SIGFPE with -Wclass-memaccess [PR105634]
Commit Message
Here we crash because we attempt to % by 0. Thus fixed.
While at it, I've moved the -Wclass-memaccess tests into warn/.
I've checked that the # of expected passes is the same before/after
the move.
Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk?
PR c++/105634
gcc/cp/ChangeLog:
* call.cc (maybe_warn_class_memaccess): Avoid % by zero.
gcc/testsuite/ChangeLog:
* g++.dg/Wclass-memaccess-2.C: Moved to...
* g++.dg/warn/Wclass-memaccess-2.C: ...here.
* g++.dg/Wclass-memaccess-3.C: Moved to...
* g++.dg/warn/Wclass-memaccess-3.C: ...here.
* g++.dg/Wclass-memaccess-4.C: Moved to...
* g++.dg/warn/Wclass-memaccess-4.C: ...here.
* g++.dg/Wclass-memaccess-5.C: Moved to...
* g++.dg/warn/Wclass-memaccess-5.C: ...here.
* g++.dg/Wclass-memaccess-6.C: Moved to...
* g++.dg/warn/Wclass-memaccess-6.C: ...here.
* g++.dg/Wclass-memaccess.C: Moved to...
* g++.dg/warn/Wclass-memaccess.C: ...here.
* g++.dg/warn/Wclass-memaccess-7.C: New test.
---
gcc/cp/call.cc | 2 ++
.../g++.dg/{ => warn}/Wclass-memaccess-2.C | 0
.../g++.dg/{ => warn}/Wclass-memaccess-3.C | 0
.../g++.dg/{ => warn}/Wclass-memaccess-4.C | 0
.../g++.dg/{ => warn}/Wclass-memaccess-5.C | 0
.../g++.dg/{ => warn}/Wclass-memaccess-6.C | 0
gcc/testsuite/g++.dg/warn/Wclass-memaccess-7.C | 13 +++++++++++++
gcc/testsuite/g++.dg/{ => warn}/Wclass-memaccess.C | 0
8 files changed, 15 insertions(+)
rename gcc/testsuite/g++.dg/{ => warn}/Wclass-memaccess-2.C (100%)
rename gcc/testsuite/g++.dg/{ => warn}/Wclass-memaccess-3.C (100%)
rename gcc/testsuite/g++.dg/{ => warn}/Wclass-memaccess-4.C (100%)
rename gcc/testsuite/g++.dg/{ => warn}/Wclass-memaccess-5.C (100%)
rename gcc/testsuite/g++.dg/{ => warn}/Wclass-memaccess-6.C (100%)
create mode 100644 gcc/testsuite/g++.dg/warn/Wclass-memaccess-7.C
rename gcc/testsuite/g++.dg/{ => warn}/Wclass-memaccess.C (100%)
base-commit: c9852156dd2fedec130f6d8eb669579ef6237946
Comments
On 5/17/22 19:57, Marek Polacek wrote:
> Here we crash because we attempt to % by 0. Thus fixed.
> While at it, I've moved the -Wclass-memaccess tests into warn/.
> I've checked that the # of expected passes is the same before/after
> the move.
>
> Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk?
OK.
> PR c++/105634
>
> gcc/cp/ChangeLog:
>
> * call.cc (maybe_warn_class_memaccess): Avoid % by zero.
>
> gcc/testsuite/ChangeLog:
>
> * g++.dg/Wclass-memaccess-2.C: Moved to...
> * g++.dg/warn/Wclass-memaccess-2.C: ...here.
> * g++.dg/Wclass-memaccess-3.C: Moved to...
> * g++.dg/warn/Wclass-memaccess-3.C: ...here.
> * g++.dg/Wclass-memaccess-4.C: Moved to...
> * g++.dg/warn/Wclass-memaccess-4.C: ...here.
> * g++.dg/Wclass-memaccess-5.C: Moved to...
> * g++.dg/warn/Wclass-memaccess-5.C: ...here.
> * g++.dg/Wclass-memaccess-6.C: Moved to...
> * g++.dg/warn/Wclass-memaccess-6.C: ...here.
> * g++.dg/Wclass-memaccess.C: Moved to...
> * g++.dg/warn/Wclass-memaccess.C: ...here.
> * g++.dg/warn/Wclass-memaccess-7.C: New test.
> ---
> gcc/cp/call.cc | 2 ++
> .../g++.dg/{ => warn}/Wclass-memaccess-2.C | 0
> .../g++.dg/{ => warn}/Wclass-memaccess-3.C | 0
> .../g++.dg/{ => warn}/Wclass-memaccess-4.C | 0
> .../g++.dg/{ => warn}/Wclass-memaccess-5.C | 0
> .../g++.dg/{ => warn}/Wclass-memaccess-6.C | 0
> gcc/testsuite/g++.dg/warn/Wclass-memaccess-7.C | 13 +++++++++++++
> gcc/testsuite/g++.dg/{ => warn}/Wclass-memaccess.C | 0
> 8 files changed, 15 insertions(+)
> rename gcc/testsuite/g++.dg/{ => warn}/Wclass-memaccess-2.C (100%)
> rename gcc/testsuite/g++.dg/{ => warn}/Wclass-memaccess-3.C (100%)
> rename gcc/testsuite/g++.dg/{ => warn}/Wclass-memaccess-4.C (100%)
> rename gcc/testsuite/g++.dg/{ => warn}/Wclass-memaccess-5.C (100%)
> rename gcc/testsuite/g++.dg/{ => warn}/Wclass-memaccess-6.C (100%)
> create mode 100644 gcc/testsuite/g++.dg/warn/Wclass-memaccess-7.C
> rename gcc/testsuite/g++.dg/{ => warn}/Wclass-memaccess.C (100%)
>
> diff --git a/gcc/cp/call.cc b/gcc/cp/call.cc
> index 0240e364324..14c6037729f 100644
> --- a/gcc/cp/call.cc
> +++ b/gcc/cp/call.cc
> @@ -10329,6 +10329,8 @@ maybe_warn_class_memaccess (location_t loc, tree fndecl,
> /* Finally, warn on partial copies. */
> unsigned HOST_WIDE_INT typesize
> = tree_to_uhwi (TYPE_SIZE_UNIT (desttype));
> + if (typesize == 0)
> + break;
> if (unsigned HOST_WIDE_INT partial = tree_to_uhwi (sz) % typesize)
> warned = warning_at (loc, OPT_Wclass_memaccess,
> (typesize - partial > 1
> diff --git a/gcc/testsuite/g++.dg/Wclass-memaccess-2.C b/gcc/testsuite/g++.dg/warn/Wclass-memaccess-2.C
> similarity index 100%
> rename from gcc/testsuite/g++.dg/Wclass-memaccess-2.C
> rename to gcc/testsuite/g++.dg/warn/Wclass-memaccess-2.C
> diff --git a/gcc/testsuite/g++.dg/Wclass-memaccess-3.C b/gcc/testsuite/g++.dg/warn/Wclass-memaccess-3.C
> similarity index 100%
> rename from gcc/testsuite/g++.dg/Wclass-memaccess-3.C
> rename to gcc/testsuite/g++.dg/warn/Wclass-memaccess-3.C
> diff --git a/gcc/testsuite/g++.dg/Wclass-memaccess-4.C b/gcc/testsuite/g++.dg/warn/Wclass-memaccess-4.C
> similarity index 100%
> rename from gcc/testsuite/g++.dg/Wclass-memaccess-4.C
> rename to gcc/testsuite/g++.dg/warn/Wclass-memaccess-4.C
> diff --git a/gcc/testsuite/g++.dg/Wclass-memaccess-5.C b/gcc/testsuite/g++.dg/warn/Wclass-memaccess-5.C
> similarity index 100%
> rename from gcc/testsuite/g++.dg/Wclass-memaccess-5.C
> rename to gcc/testsuite/g++.dg/warn/Wclass-memaccess-5.C
> diff --git a/gcc/testsuite/g++.dg/Wclass-memaccess-6.C b/gcc/testsuite/g++.dg/warn/Wclass-memaccess-6.C
> similarity index 100%
> rename from gcc/testsuite/g++.dg/Wclass-memaccess-6.C
> rename to gcc/testsuite/g++.dg/warn/Wclass-memaccess-6.C
> diff --git a/gcc/testsuite/g++.dg/warn/Wclass-memaccess-7.C b/gcc/testsuite/g++.dg/warn/Wclass-memaccess-7.C
> new file mode 100644
> index 00000000000..7e86b248629
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/warn/Wclass-memaccess-7.C
> @@ -0,0 +1,13 @@
> +// PR c++/105634
> +// { dg-do compile { target { c++11 } } }
> +// { dg-options "-Wall" }
> +
> +struct s
> +{
> + struct {} a[] = 1.0; // { dg-error "" }
> + void f (char *c)
> + {
> + s s;
> + __builtin_memcpy (&s, c, sizeof(s));
> + }
> +};
> diff --git a/gcc/testsuite/g++.dg/Wclass-memaccess.C b/gcc/testsuite/g++.dg/warn/Wclass-memaccess.C
> similarity index 100%
> rename from gcc/testsuite/g++.dg/Wclass-memaccess.C
> rename to gcc/testsuite/g++.dg/warn/Wclass-memaccess.C
>
> base-commit: c9852156dd2fedec130f6d8eb669579ef6237946
@@ -10329,6 +10329,8 @@ maybe_warn_class_memaccess (location_t loc, tree fndecl,
/* Finally, warn on partial copies. */
unsigned HOST_WIDE_INT typesize
= tree_to_uhwi (TYPE_SIZE_UNIT (desttype));
+ if (typesize == 0)
+ break;
if (unsigned HOST_WIDE_INT partial = tree_to_uhwi (sz) % typesize)
warned = warning_at (loc, OPT_Wclass_memaccess,
(typesize - partial > 1
similarity index 100%
rename from gcc/testsuite/g++.dg/Wclass-memaccess-2.C
rename to gcc/testsuite/g++.dg/warn/Wclass-memaccess-2.C
similarity index 100%
rename from gcc/testsuite/g++.dg/Wclass-memaccess-3.C
rename to gcc/testsuite/g++.dg/warn/Wclass-memaccess-3.C
similarity index 100%
rename from gcc/testsuite/g++.dg/Wclass-memaccess-4.C
rename to gcc/testsuite/g++.dg/warn/Wclass-memaccess-4.C
similarity index 100%
rename from gcc/testsuite/g++.dg/Wclass-memaccess-5.C
rename to gcc/testsuite/g++.dg/warn/Wclass-memaccess-5.C
similarity index 100%
rename from gcc/testsuite/g++.dg/Wclass-memaccess-6.C
rename to gcc/testsuite/g++.dg/warn/Wclass-memaccess-6.C
new file mode 100644
@@ -0,0 +1,13 @@
+// PR c++/105634
+// { dg-do compile { target { c++11 } } }
+// { dg-options "-Wall" }
+
+struct s
+{
+ struct {} a[] = 1.0; // { dg-error "" }
+ void f (char *c)
+ {
+ s s;
+ __builtin_memcpy (&s, c, sizeof(s));
+ }
+};
similarity index 100%
rename from gcc/testsuite/g++.dg/Wclass-memaccess.C
rename to gcc/testsuite/g++.dg/warn/Wclass-memaccess.C