Don't compare pointer against '0', but NULL
diff --git a/src/stdlib/SDL_qsort.c b/src/stdlib/SDL_qsort.c
index b0f92fd..d17b6a3 100644
--- a/src/stdlib/SDL_qsort.c
+++ b/src/stdlib/SDL_qsort.c
@@ -414,7 +414,7 @@ static void qsort_nonaligned(void *base, size_t nmemb, size_t size,
char *first,*last;
char *pivot=malloc(size);
size_t trunc=TRUNC_nonaligned*size;
- assert(pivot);
+ assert(pivot != NULL);
first=(char*)base; last=first+(nmemb-1)*size;
@@ -445,7 +445,7 @@ static void qsort_aligned(void *base, size_t nmemb, size_t size,
char *first,*last;
char *pivot=malloc(size);
size_t trunc=TRUNC_aligned*size;
- assert(pivot);
+ assert(pivot != NULL);
first=(char*)base; last=first+(nmemb-1)*size;
@@ -475,7 +475,7 @@ static void qsort_words(void *base, size_t nmemb,
int stacktop=0;
char *first,*last;
char *pivot=malloc(WORD_BYTES);
- assert(pivot);
+ assert(pivot != NULL);
first=(char*)base; last=first+(nmemb-1)*WORD_BYTES;