File gdb-ppc64-stwux-tautological-compare.patch of Package gdb

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File gdb-ppc64-stwux-tautological-compare.patch of Package gdb (Revision c65fd6bedbc211ad1b746c77641a5624)

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From FEDORA_PATCHES Mon Sep 17 00:00:00 2001
From: Jan Kratochvil <jan.kratochvil@redhat.com>
Date: Sun, 4 Feb 2018 21:42:18 +0100
Subject: gdb-ppc64-stwux-tautological-compare.patch

FileName: gdb-ppc64-stwux-tautological-compare.patch

;; Fix ppc64 stwux encoding as found by gcc-8.0 -Werror=tautological-compare.

[patch] ppc64: Fix stwux encoding
https://sourceware.org/ml/gdb-patches/2018-02/msg00058.html

with gcc-8.0.1-0.9.fc28.x86_64 I get:

../../gdb/rs6000-tdep.c: In function 'CORE_ADDR skip_prologue(gdbarch*, CORE_ADDR, CORE_ADDR, rs6000_framedata*)':
../../gdb/rs6000-tdep.c:1911:34: error: bitwise comparison always evaluates to false [-Werror=tautological-compare]
       else if ((op & 0xfc1f016a) == 0x7c01016e)
                ~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~

The code is there since:
	commit 98f08d3d9b69b344bb8b0cd2a4bda1cf4d966e20
	Author: Kevin Buettner <kevinb@redhat.com>
	Date:   Thu May 29 19:47:14 2003 +0000
		    From Jimi X <jimix@watson.ibm.com>:
		    * rs6000-tdep.c (skip_prologue): Improve support for 64-bit code.
So I do not think we can find the original author.

https://www.ibm.com/support/knowledgecenter/en/ssw_aix_72/com.ibm.aix.alangref/idalangref_stwux_stux_instrs.htm
says
	bit 21 - 30 = 183
	Those are bits 1..10 in normal bit order: 183<<1 = 0x16e

gdb/ChangeLog
2018-02-04  Jan Kratochvil  <jan.kratochvil@redhat.com>

* rs6000-tdep.c (skip_prologue): Fix stwux encoding.
---
 gdb/rs6000-tdep.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gdb/rs6000-tdep.c b/gdb/rs6000-tdep.c
index 23d0db3b8f..5275ff5b91 100644
--- a/gdb/rs6000-tdep.c
+++ b/gdb/rs6000-tdep.c
@@ -1908,7 +1908,7 @@ skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc, CORE_ADDR lim_pc,
 	  offset = fdata->offset;
 	  continue;
 	}
-      else if ((op & 0xfc1f016a) == 0x7c01016e)
+      else if ((op & 0xfc1f016e) == 0x7c01016e)
 	{			/* stwux rX,r1,rY */
 	  /* No way to figure out what r1 is going to be.  */
 	  fdata->frameless = 0;
-- 
2.14.3

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File gdb-ppc64-stwux-tautological-compare.patch of Package gdb (Revision c65fd6bedbc211ad1b746c77641a5624)

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