public inbox for gcc-cvs@sourceware.org
help / color / mirror / Atom feed
* [gcc(refs/users/marxin/heads/marxin-gcc-benchmark-branch)] c: Fix ICE with cast to VLA [93576]
@ 2020-03-30 11:02 Martin Liska
0 siblings, 0 replies; only message in thread
From: Martin Liska @ 2020-03-30 11:02 UTC (permalink / raw)
To: gcc-cvs
https://gcc.gnu.org/g:bacdd5e978dad84e9c547b0d5c7fed14b8d75157
commit bacdd5e978dad84e9c547b0d5c7fed14b8d75157
Author: Jakub Jelinek <jakub@redhat.com>
Date: Thu Feb 13 21:00:09 2020 +0100
c: Fix ICE with cast to VLA [93576]
The following testcase ICEs, because the PR84305 changes try to evaluate
the size earlier. If size has side-effects, that is desirable, and the
side-effects will actually be wrapped in a SAVE_EXPR. The problem on this
testcase is that there are no side-effects, and c_fully_fold doesn't fold
those COMPOUND_EXPRs to constant, and while before gimplification we unshare
trees found in the expressions, the unsharing doesn't involve TYPE_SIZE etc.
of used types. Gimplification is destructive though, so when we gimplify
the two nested COMPOUND_EXPRs and then try to gimplify it the second time
for the TYPE_SIZEs, we ICE.
Now, we could use unshare_expr in what we push to *expr, SAVE_EXPRs and
their operands in there aren't unshared, but I really don't see a point of
evaluating expressions that don't have side-effects before, so instead
this just pushes there expressions that do have side-effects.
2020-02-13 Jakub Jelinek <jakub@redhat.com>
PR c/93576
* c-decl.c (grokdeclarator): If this_size_varies, only push size into
*expr if it has side effects.
* gcc.dg/pr93576.c: New test.
Diff:
---
gcc/c/ChangeLog | 6 ++++++
gcc/c/c-decl.c | 13 ++++++++-----
gcc/testsuite/ChangeLog | 5 +++++
gcc/testsuite/gcc.dg/pr93576.c | 10 ++++++++++
4 files changed, 29 insertions(+), 5 deletions(-)
diff --git a/gcc/c/ChangeLog b/gcc/c/ChangeLog
index 995f315a803..e88337b18a0 100644
--- a/gcc/c/ChangeLog
+++ b/gcc/c/ChangeLog
@@ -1,3 +1,9 @@
+2020-02-13 Jakub Jelinek <jakub@redhat.com>
+
+ PR c/93576
+ * c-decl.c (grokdeclarator): If this_size_varies, only push size into
+ *expr if it has side effects.
+
2020-01-30 Jeff Law <law@redhat.com>
PR c/88660
diff --git a/gcc/c/c-decl.c b/gcc/c/c-decl.c
index 8281af7307a..1aa410db6e4 100644
--- a/gcc/c/c-decl.c
+++ b/gcc/c/c-decl.c
@@ -6512,11 +6512,14 @@ grokdeclarator (const struct c_declarator *declarator,
}
if (this_size_varies)
{
- if (*expr)
- *expr = build2 (COMPOUND_EXPR, TREE_TYPE (size),
- *expr, size);
- else
- *expr = size;
+ if (TREE_SIDE_EFFECTS (size))
+ {
+ if (*expr)
+ *expr = build2 (COMPOUND_EXPR, TREE_TYPE (size),
+ *expr, size);
+ else
+ *expr = size;
+ }
*expr_const_operands &= size_maybe_const;
}
}
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 560187c701a..a262bdde886 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2020-02-13 Jakub Jelinek <jakub@redhat.com>
+
+ PR c/93576
+ * gcc.dg/pr93576.c: New test.
+
2020-02-13 Sandra Loosemore <sandra@codesourcery.com>
* g++.dg/cpp0x/constexpr-static13.C:
diff --git a/gcc/testsuite/gcc.dg/pr93576.c b/gcc/testsuite/gcc.dg/pr93576.c
new file mode 100644
index 00000000000..13c34f3771f
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr93576.c
@@ -0,0 +1,10 @@
+/* PR c/93576 */
+/* { dg-do compile } */
+/* { dg-options "" } */
+
+void
+foo (void)
+{
+ int b[] = { 0 };
+ (char (*)[(1, 7, 2)]) 0;
+}
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2020-03-30 11:02 UTC | newest]
Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-03-30 11:02 [gcc(refs/users/marxin/heads/marxin-gcc-benchmark-branch)] c: Fix ICE with cast to VLA [93576] Martin Liska
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).