malloc: cast size down to int in bin_index functions

[musl] / src / malloc / malloc.c

diff --git a/src/malloc/malloc.c b/src/malloc/malloc.c
index ee6f170..207b6ef 100644 (file)
--- a/src/malloc/malloc.c
+++ b/src/malloc/malloc.c
@@ -1,3 +1,4 @@
+#define _GNU_SOURCE
 #include <stdlib.h>
 #include <string.h>
 #include <limits.h>
@@ -119,14 +120,14 @@ static int bin_index(size_t x)
        x = x / SIZE_ALIGN - 1;
        if (x <= 32) return x;
        if (x > 0x1c00) return 63;
-       return ((union { float v; uint32_t r; }){ x }.r>>21) - 496;
+       return ((union { float v; uint32_t r; }){(int)x}.r>>21) - 496;
 }
 
 static int bin_index_up(size_t x)
 {
        x = x / SIZE_ALIGN - 1;
        if (x <= 32) return x;
-       return ((union { float v; uint32_t r; }){ x }.r+0x1fffff>>21) - 496;
+       return ((union { float v; uint32_t r; }){(int)x}.r+0x1fffff>>21) - 496;
 }
 
 #if 0
@@ -333,7 +334,7 @@ void *malloc(size_t n)
        if (adjust_size(&n) < 0) return 0;
 
        if (n > MMAP_THRESHOLD) {
-               size_t len = n + PAGE_SIZE - 1 & -PAGE_SIZE;
+               size_t len = n + OVERHEAD + PAGE_SIZE - 1 & -PAGE_SIZE;
                char *base = __mmap(0, len, PROT_READ|PROT_WRITE,
                        MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
                if (base == (void *)-1) return 0;
@@ -394,7 +395,7 @@ void *realloc(void *p, size_t n)
                size_t oldlen = n0 + extra;
                size_t newlen = n + extra;
                /* Crash on realloc of freed chunk */
-               if ((uintptr_t)base < mal.brk) *(char *)0=0;
+               if ((uintptr_t)base < mal.brk) *(volatile char *)0=0;
                if (newlen < PAGE_SIZE && (new = malloc(n))) {
                        memcpy(new, p, n-OVERHEAD);
                        free(p);
@@ -457,7 +458,7 @@ void free(void *p)
                char *base = (char *)self - extra;
                size_t len = CHUNK_SIZE(self) + extra;
                /* Crash on double free */
-               if ((uintptr_t)base < mal.brk) *(char *)0=0;
+               if ((uintptr_t)base < mal.brk) *(volatile char *)0=0;
                __munmap(base, len);
                return;
        }