This is the mail archive of the
libc-alpha@sourceware.org
mailing list for the glibc project.
[PATCH] arm: Use nr constraint for Systemtap probes [BZ #24164]
- From: Florian Weimer <fweimer at redhat dot com>
- To: libc-alpha at sourceware dot org
- Date: Mon, 04 Feb 2019 14:52:08 +0100
- Subject: [PATCH] arm: Use nr constraint for Systemtap probes [BZ #24164]
With the default "nor" constraint, current GCC will use the "o"
constraint for constants, after emitting the constant to memory. That
results in unparseable Systemtap probe notes such as "-4@.L1052".
Removing the "o" alternative and using "nr" instead avoids this.
2019-02-04 Florian Weimer <fweimer@redhat.com>
[BZ #24164]
arm: Use "nr" constraint for Systemtap probes, to avoid the
compiler using memory operands for constants, due to the "o"
alternative in the default "nor" constraint.
* include/stap-probe.h [USE_STAP_PROBE]: Include
<stap-probe-machine.h>
* sysdeps/generic/stap-probe-machine.h: New file.
* sysdeps/arm/stap-probe-machine.h: Likewise.
diff --git a/include/stap-probe.h b/include/stap-probe.h
index c53dd86592..8c26292edd 100644
--- a/include/stap-probe.h
+++ b/include/stap-probe.h
@@ -21,6 +21,7 @@
#ifdef USE_STAP_PROBE
+# include <stap-probe-machine.h>
# include <sys/sdt.h>
/* Our code uses one macro LIBC_PROBE (name, n, arg1, ..., argn).
diff --git a/sysdeps/arm/stap-probe-machine.h b/sysdeps/arm/stap-probe-machine.h
new file mode 100644
index 0000000000..b15855ab37
--- /dev/null
+++ b/sysdeps/arm/stap-probe-machine.h
@@ -0,0 +1,22 @@
+/* Macros for customizing Systemtap <sys/sdt.h>. Arm version.
+ Copyright (C) 2019 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+/* The default "nor" constraint produces unparseable memory references
+ for constants. Omit the problematic "o" constraint. See bug 24164
+ and GCC 89146. */
+#define STAP_SDT_ARG_CONSTRAINT nr
diff --git a/sysdeps/generic/stap-probe-machine.h b/sysdeps/generic/stap-probe-machine.h
new file mode 100644
index 0000000000..aa4e29c42e
--- /dev/null
+++ b/sysdeps/generic/stap-probe-machine.h
@@ -0,0 +1,19 @@
+/* Macros for customizing Systemtap <sys/sdt.h>. Generic version.
+ Copyright (C) 2019 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+/* By default, there are no custimizations. */