Module Name: src
Committed By: rillig
Date: Sun Sep 27 16:38:32 UTC 2020
Modified Files:
src/usr.bin/make: buf.h
Log Message:
make(1): prefer positive array index in Buf_AddByte
Ideally the condition for allocating more memory would have been
(old_len + 2 > bp->cap) since that's the actually intended wording. But
GCC 5 neglected to generate good code for that on x86_64, so be it.
To generate a diff of this commit:
cvs rdiff -u -r1.31 -r1.32 src/usr.bin/make/buf.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/usr.bin/make/buf.h
diff -u src/usr.bin/make/buf.h:1.31 src/usr.bin/make/buf.h:1.32
--- src/usr.bin/make/buf.h:1.31 Sun Sep 27 16:21:06 2020
+++ src/usr.bin/make/buf.h Sun Sep 27 16:38:32 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: buf.h,v 1.31 2020/09/27 16:21:06 rillig Exp $ */
+/* $NetBSD: buf.h,v 1.32 2020/09/27 16:38:32 rillig Exp $ */
/*
* Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
@@ -97,13 +97,13 @@ void Buf_Expand_1(Buffer *);
static inline MAKE_ATTR_UNUSED void
Buf_AddByte(Buffer *bp, char byte)
{
- size_t new_len = ++bp->len;
- char *end_plus_one;
- if (__predict_false(new_len >= bp->cap))
+ size_t old_len = bp->len++;
+ char *end;
+ if (__predict_false(old_len + 1 >= bp->cap))
Buf_Expand_1(bp);
- end_plus_one = bp->data + new_len;
- end_plus_one[-1] = byte;
- end_plus_one[0] = 0;
+ end = bp->data + old_len;
+ end[0] = byte;
+ end[1] = '\0';
}
static inline MAKE_ATTR_UNUSED size_t
