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From: "anlauf at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug fortran/99218] matmul on temporary array accesses invalid memory (segfault)
Date: Tue, 23 Feb 2021 21:10:33 +0000 [thread overview]
Message-ID: <bug-99218-4-aBeoFboZ00@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-99218-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99218
anlauf at gcc dot gnu.org changed:
What |Removed |Added
----------------------------------------------------------------------------
Known to fail| |8.4.1
--- Comment #3 from anlauf at gcc dot gnu.org ---
Playing with the reduced testcase:
fTmp = matmul (transpose (G), lambda(::2))
is clean while
fTmp = matmul (transpose (G), lambda(::1))
is not.
It seems we run into a highly optimized code for rank-2 times rank-2.
The following patch fixes the testcase:
diff --git a/libgfortran/m4/matmul_internal.m4
b/libgfortran/m4/matmul_internal.m4
index 13fd7696238..0e96207a0fc 100644
--- a/libgfortran/m4/matmul_internal.m4
+++ b/libgfortran/m4/matmul_internal.m4
@@ -192,7 +192,8 @@ sinclude(`matmul_asm_'rtype_code`.m4')dnl
}
}
- if (rxstride == 1 && axstride == 1 && bxstride == 1)
+ if (rxstride == 1 && axstride == 1 && bxstride == 1
+ && GFC_DESCRIPTOR_RANK (b) != 1)
{
/* This block of code implements a tuned matmul, derived from
Superscalar GEMM-based level 3 BLAS, Beta version 0.1
next prev parent reply other threads:[~2021-02-23 21:10 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-23 14:16 [Bug fortran/99218] New: " rpmcnally at gmail dot com
2021-02-23 20:07 ` [Bug fortran/99218] " anlauf at gcc dot gnu.org
2021-02-23 20:27 ` anlauf at gcc dot gnu.org
2021-02-23 21:10 ` anlauf at gcc dot gnu.org [this message]
2021-02-23 21:18 ` [Bug libfortran/99218] [8/9/19/11 Regression] " anlauf at gcc dot gnu.org
2021-02-23 21:47 ` anlauf at gcc dot gnu.org
2021-02-23 21:47 ` [Bug libfortran/99218] [8/9/10/11 " anlauf at gcc dot gnu.org
2021-03-05 19:59 ` cvs-commit at gcc dot gnu.org
2021-03-06 17:23 ` cvs-commit at gcc dot gnu.org
2021-03-07 19:42 ` cvs-commit at gcc dot gnu.org
2021-03-07 20:27 ` cvs-commit at gcc dot gnu.org
2021-03-07 20:28 ` anlauf at gcc dot gnu.org
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