From: Julian Seward <jseward@acm.org>
Date: Tue, 7 Nov 2017 14:01:51 +0000 (+0100)
Subject: s390_irgen_EX_SS: add initialisations so as to remove (false positive) warnings from... 
X-Git-Tag: VALGRIND_3_14_0~206
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d813fb74af762393a43dd9c70882e655f35ec2ca;p=thirdparty%2Fvalgrind.git

s390_irgen_EX_SS: add initialisations so as to remove (false positive) warnings from gcc-7.x.

When compiling guest_s390_toIR.c for a 32-bit target (a configuration in which
it will never be used, but never mind), gcc-7.x notices that sizeof(ss.dec) is
larger than sizeof(ss.bytes), so the initialisation of ss.bytes leaves ss.dec.b2
and ss.dec.d2 uninitialised.  This patch causes both variants to be initialised.
When built for a 64 bit target, the existing initialisation of ss.bytes covers
ss.dec completely, so there is no error.
---

diff --git a/VEX/priv/guest_s390_toIR.c b/VEX/priv/guest_s390_toIR.c
index 14c8950826..b36b85e918 100644
--- a/VEX/priv/guest_s390_toIR.c
+++ b/VEX/priv/guest_s390_toIR.c
@@ -11078,6 +11078,7 @@ s390_irgen_EX_SS(UChar r, IRTemp addr2,
    stmt(IRStmt_Put(S390X_GUEST_OFFSET(guest_CMLEN), mkU64(4)));
    restart_if(mkexpr(cond));
 
+   ss.dec.op = ss.dec.l = ss.dec.b1 = ss.dec.d1 = ss.dec.b2 = ss.dec.d2 = 0;
    ss.bytes = last_execute_target;
    assign(start1, binop(Iop_Add64, mkU64(ss.dec.d1),
           ss.dec.b1 != 0 ? get_gpr_dw0(ss.dec.b1) : mkU64(0)));