RtsUtils: Use `size_t` instead of `int` where appropriate

Functions like `stgMallocBytes` take a size parameter which was of type
`int`, but is commonly used as `stgMallocBytes (sizeof (...))`. This is
problematic because the `sizeof` operator returns `size_t` so that on 64 bit
systems, in this common use case the `size_t` parameter would be truncated to
32 bits when passed to `stgMallocBytes` where it was cast back to `size_t`.

2 files changed, 12 insertions, 16 deletions

diff --git a/rts/RtsUtils.c b/rts/RtsUtils.c
index c83714337e..716d203462 100644
--- a/rts/RtsUtils.c
+++ b/rts/RtsUtils.c
@@ -57,13 +57,11 @@ extern char *ctime_r(const time_t *, char *);
    -------------------------------------------------------------------------- */
 
 void *
-stgMallocBytes (int n, char *msg)
+stgMallocBytes (size_t n, char *msg)
 {
-    char *space;
-    size_t n2;
+    void *space;
 
-    n2 = (size_t) n;
-    if ((space = (char *) malloc(n2)) == NULL) {
+    if ((space = malloc(n)) == NULL) {
       /* Quoting POSIX.1-2008 (which says more or less the same as ISO C99):
        *
        *   "Upon successful completion with size not equal to 0, malloc() shall
@@ -85,13 +83,11 @@ stgMallocBytes (int n, char *msg)
 }
 
 void *
-stgReallocBytes (void *p, int n, char *msg)
+stgReallocBytes (void *p, size_t n, char *msg)
 {
-    char *space;
-    size_t n2;
+    void *space;
 
-    n2 = (size_t) n;
-    if ((space = (char *) realloc(p, (size_t) n2)) == NULL) {
+    if ((space = realloc(p, n)) == NULL) {
       /* don't fflush(stdout); WORKAROUND bug in Linux glibc */
       rtsConfig.mallocFailHook((W_) n, msg); /*msg*/
       stg_exit(EXIT_INTERNAL_ERROR);
@@ -100,11 +96,11 @@ stgReallocBytes (void *p, int n, char *msg)
 }
 
 void *
-stgCallocBytes (int n, int m, char *msg)
+stgCallocBytes (size_t n, size_t m, char *msg)
 {
-    char *space;
+    void *space;
 
-    if ((space = (char *) calloc((size_t) n, (size_t) m)) == NULL) {
+    if ((space = calloc(n, m)) == NULL) {
       /* don't fflush(stdout); WORKAROUND bug in Linux glibc */
       rtsConfig.mallocFailHook((W_) n*m, msg); /*msg*/
       stg_exit(EXIT_INTERNAL_ERROR);
diff --git a/rts/RtsUtils.h b/rts/RtsUtils.h
index d76c921a36..2d5e5de02c 100644
--- a/rts/RtsUtils.h
+++ b/rts/RtsUtils.h
@@ -18,12 +18,12 @@
 void initAllocator(void);
 void shutdownAllocator(void);
 
-void *stgMallocBytes(int n, char *msg)
+void *stgMallocBytes(size_t n, char *msg)
     GNUC3_ATTRIBUTE(__malloc__);
 
-void *stgReallocBytes(void *p, int n, char *msg);
+void *stgReallocBytes(void *p, size_t n, char *msg);
 
-void *stgCallocBytes(int n, int m, char *msg)
+void *stgCallocBytes(size_t n, size_t m, char *msg)
      GNUC3_ATTRIBUTE(__malloc__);
 
 char *stgStrndup(const char *s, size_t n);