harec

commit d4a76426e90c290714e5ff016b341cbf8e7da380
parent 57a023e2f2d252a773cd0e9a24f9aa3057f6ad90
Author: Drew DeVault <sir@cmpwn.com>
Date:   Fri, 12 Feb 2021 14:06:37 -0500

Fix allocation of empty slices

Diffstat:
M
rt/malloc.ha
 | 
2
+-
M
tests/17-alloc.ha
 | 
8
++++++++

2 files changed, 9 insertions(+), 1 deletion(-)
diff --git a/rt/malloc.ha b/rt/malloc.ha
@@ -52,7 +52,7 @@ let nfree: int = 0;
 // Allocates n bytes of memory and returns a pointer to them, or null if there
 // is insufficient memory.
 export fn malloc(n: size) nullable *void = {
-	assert(n > 0);
+	if (n == 0) return null;
 	let r = if (n > bin2size(len(bins) - 1)) malloc_large(n)
 		else malloc_small(n);
 	nalloc += 1;
diff --git a/tests/17-alloc.ha b/tests/17-alloc.ha
@@ -64,6 +64,14 @@ fn slice() void = {
 		assert(y[i] == (i + 1): int);
 	};
 	free(y);
+
+	let z = alloc([]int, []);
+	let p = &z: *struct {
+		data: nullable *[*]int,
+		length: size,
+		capacity: size,
+	};
+	assert(p.data == null && p.length == 0 && p.capacity == 0);
 };
 
 fn string() void = {