From 6034406eae500a10ed9bb4085559935cda275ec0 Mon Sep 17 00:00:00 2001
From: Russ Cox <rsc@golang.org>
Date: Tue, 10 Sep 2013 14:54:55 -0400
Subject: [PATCH] build: more "undefined behavior" fixes

Fixes #5764.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/13441051
---
 src/cmd/6g/gsubr.c | 2 +-
 src/cmd/6l/obj.c   | 2 +-
 src/cmd/6l/span.c  | 2 ++
 src/libbio/bgetc.c | 2 +-
 4 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/cmd/6g/gsubr.c b/src/cmd/6g/gsubr.c
index 0e45cc0ebe5..e68a0899e9d 100644
--- a/src/cmd/6g/gsubr.c
+++ b/src/cmd/6g/gsubr.c
@@ -540,7 +540,7 @@ ginscon(int as, vlong c, Node *n2)
 
 	nodconst(&n1, types[TINT64], c);
 
-	if(as != AMOVQ && (c < -1LL<<31 || c >= 1LL<<31)) {
+	if(as != AMOVQ && (c < -(1LL<<31) || c >= 1LL<<31)) {
 		// cannot have 64-bit immediokate in ADD, etc.
 		// instead, MOV into register first.
 		regalloc(&ntmp, types[TINT64], N);
diff --git a/src/cmd/6l/obj.c b/src/cmd/6l/obj.c
index 12ca0f63501..a12b6e6f9ba 100644
--- a/src/cmd/6l/obj.c
+++ b/src/cmd/6l/obj.c
@@ -346,7 +346,7 @@ zaddr(char *pn, Biobuf *f, Adr *a, Sym *h[])
 		a->offset = BGETLE4(f);
 		if(t & T_64) {
 			a->offset &= 0xFFFFFFFFULL;
-			a->offset |= (vlong)BGETLE4(f) << 32;
+			a->offset |= (uvlong)BGETLE4(f) << 32;
 		}
 	}
 	a->sym = S;
diff --git a/src/cmd/6l/span.c b/src/cmd/6l/span.c
index 9fad0eed0ac..74f11d635a8 100644
--- a/src/cmd/6l/span.c
+++ b/src/cmd/6l/span.c
@@ -1237,6 +1237,8 @@ found:
 		break;
 	}
 
+	if(z >= nelem(o->op))
+		sysfatal("asmins bad table %P", p);
 	op = o->op[z];
 	if(op == 0x0f) {
 		*andptr++ = op;
diff --git a/src/libbio/bgetc.c b/src/libbio/bgetc.c
index f3db0f3029c..3399fb16b31 100644
--- a/src/libbio/bgetc.c
+++ b/src/libbio/bgetc.c
@@ -83,7 +83,7 @@ Bgetle4(Biobuf *bp)
 
 	l = Bgetle2(bp);
 	h = Bgetle2(bp);
-	return l|(h<<16);
+	return l|((uint32)h<<16);
 }
 
 int