runtime: remove unused variable

Left over from cl/119490044.

LGTM=bradfitz
R=rsc, bradfitz
CC=golang-codereviews
https://golang.org/cl/125730043

diff --git a/src/pkg/runtime/mcentral.c b/src/pkg/runtime/mcentral.c
index 5699d11ee6bd702ffe7f0c70f2d1e207a6a8b923..3f64b5ed23ebcc873a90dccb470b5b3288eef171 100644 (file)
--- a/src/pkg/runtime/mcentral.c
+++ b/src/pkg/runtime/mcentral.c
@@ -169,7 +169,7 @@ runtime·MCentral_FreeSpan(MCentral *c, MSpan *s, int32 n, MLink *start, MLink *
 static bool
 MCentral_Grow(MCentral *c)
 {
-       uintptr size, npages, cap, i, n;
+       uintptr size, npages, i, n;
        MLink **tailp, *v;
        byte *p;
        MSpan *s;