1 files changed, 17 insertions, 2 deletions

diff --git a/csv.c b/csv.c
index a4f9b51..2b39be0 100644
--- a/csv.c
+++ b/csv.c
@@ -12,6 +12,17 @@
 #define CSV_DEFAULT_SEPARATOR ','
 #endif
 
+#if defined(__GNUC__) || defined(__clang__)
+#define mul_overflow __builtin_mul_overflow
+#else
+static inline int
+mul_overflow(size_t a, size_t b, size_t *out)
+{
+    *out = a * b;
+    return ( a != 0 && (*out / a) != b );
+}
+#endif
+
 // === CSV-MEMORY Interface ===
 
 static void *
@@ -19,7 +30,11 @@ csv_mem_allocate(size_t n, size_t sz, void *cb_arg)
 {
         (void) cb_arg;
 
-        return calloc(n, sz);
+        size_t len;
+        if ( mul_overflow(n, sz, &len) ) {
+                return NULL;
+        }
+        return malloc(len);
 }
 
 static void *
@@ -28,7 +43,7 @@ csv_mem_reallocate(void *ptr, size_t n, size_t sz, void *cb_arg)
         (void) cb_arg;
 
         size_t len;
-        if ( __builtin_mul_overflow(n, sz, &len) ) {
+        if ( mul_overflow(n, sz, &len) ) {
                 return NULL;
         }
         return realloc(ptr, len);