diff --git a/tests/checkasm/Makefile b/tests/checkasm/Makefile
index 9498ebfc7fc60176e34dbe0b11b14d9f6a7ebe11..ff57aa879a6697ec0cafe25fe2c9d78928f7c45d 100644
--- a/tests/checkasm/Makefile
+++ b/tests/checkasm/Makefile
@@ -17,9 +17,6 @@ CHECKASMDIRS := $(sort $(dir $(CHECKASMOBJS)))
 $(CHECKASMOBJS): | $(CHECKASMDIRS)
 OBJDIRS += $(CHECKASMDIRS)
 
-# We rely on function pointers intentionally declared without specified argument types.
-tests/checkasm/%.o: CFLAGS := $(CFLAGS:-Wstrict-prototypes=-Wno-strict-prototypes)
-
 CHECKASM := tests/checkasm/checkasm$(EXESUF)
 
 $(CHECKASM): $(EXEOBJS) $(CHECKASMOBJS) $(FF_STATIC_DEP_LIBS)
diff --git a/tests/checkasm/bswapdsp.c b/tests/checkasm/bswapdsp.c
index 748a886ec98296324efc53133ba9a8ba56aba683..829ebaa8a803e931f4df050c8b0bc86b335e0816 100644
--- a/tests/checkasm/bswapdsp.c
+++ b/tests/checkasm/bswapdsp.c
@@ -43,6 +43,8 @@
 #define check_bswap(type)                                                                  \
     do {                                                                                   \
         int w;                                                                             \
+        declare_func(void, type *dst, const type *src, int w);                             \
+                                                                                           \
         for (w = 0; w < BUF_SIZE / sizeof(type); w++) {                                    \
             int offset = (BUF_SIZE / sizeof(type) - w) & 15; /* Test various alignments */ \
             randomize_buffers();                                                           \
diff --git a/tests/checkasm/checkasm.c b/tests/checkasm/checkasm.c
index b564e7e98816a54f768fd1ce69e8f8bc08bec767..a120bc3d3cdc188d3fdb839cdc0c2c389e473751 100644
--- a/tests/checkasm/checkasm.c
+++ b/tests/checkasm/checkasm.c
@@ -111,7 +111,7 @@ static const struct {
 
 typedef struct CheckasmFuncVersion {
     struct CheckasmFuncVersion *next;
-    intptr_t (*func)();
+    void *func;
     int ok;
     int cpu;
     int iterations;
@@ -387,10 +387,10 @@ int main(int argc, char *argv[])
 /* Decide whether or not the specified function needs to be tested and
  * allocate/initialize data structures if needed. Returns a pointer to a
  * reference function if the function should be tested, otherwise NULL */
-intptr_t (*checkasm_check_func(intptr_t (*func)(), const char *name, ...))()
+void *checkasm_check_func(void *func, const char *name, ...)
 {
     char name_buf[256];
-    intptr_t (*ref)() = func;
+    void *ref = func;
     CheckasmFuncVersion *v;
     int name_length;
     va_list arg;
diff --git a/tests/checkasm/checkasm.h b/tests/checkasm/checkasm.h
index 443546ad739f8c9ce923122c4f1a729edd64eefb..cbf3dcaee5c1e1f64fe07e25ed27c7e5b983cbfa 100644
--- a/tests/checkasm/checkasm.h
+++ b/tests/checkasm/checkasm.h
@@ -33,7 +33,7 @@ void checkasm_check_bswapdsp(void);
 void checkasm_check_h264pred(void);
 void checkasm_check_h264qpel(void);
 
-intptr_t (*checkasm_check_func(intptr_t (*func)(), const char *name, ...))() av_printf_format(2, 3);
+void *checkasm_check_func(void *func, const char *name, ...) av_printf_format(2, 3);
 int checkasm_bench_func(void);
 void checkasm_fail_func(const char *msg, ...) av_printf_format(1, 2);
 void checkasm_update_bench(int iterations, uint64_t cycles);
@@ -42,14 +42,16 @@ void checkasm_report(const char *name, ...) av_printf_format(1, 2);
 extern AVLFG checkasm_lfg;
 #define rnd() av_lfg_get(&checkasm_lfg)
 
-static av_unused intptr_t (*func_ref)();
-static av_unused intptr_t (*func_new)();
+static av_unused void *func_ref, *func_new;
 
 #define BENCH_RUNS 1000 /* Trade-off between accuracy and speed */
 
 /* Decide whether or not the specified function needs to be tested */
-#define check_func(func, ...) ((func_new = (intptr_t (*)())func) &&\
-                              (func_ref = checkasm_check_func(func_new, __VA_ARGS__)))
+#define check_func(func, ...) (func_ref = checkasm_check_func((func_new = func), __VA_ARGS__))
+
+/* Declare the function prototype. The first argument is the return value, the remaining
+ * arguments are the function parameters. Naming parameters is optional. */
+#define declare_func(ret, ...) declare_new(ret, __VA_ARGS__) typedef ret func_type(__VA_ARGS__)
 
 /* Indicate that the current test has failed */
 #define fail() checkasm_fail_func("%s:%d", av_basename(__FILE__), __LINE__)
@@ -58,18 +60,16 @@ static av_unused intptr_t (*func_new)();
 #define report checkasm_report
 
 /* Call the reference function */
-#define call_ref(...) func_ref(__VA_ARGS__)
+#define call_ref(...) ((func_type *)func_ref)(__VA_ARGS__)
 
 #if ARCH_X86 && HAVE_YASM
 /* Verifies that clobbered callee-saved registers are properly saved and restored */
-intptr_t checkasm_checked_call(intptr_t (*func)(), ...);
-#endif
+void checkasm_checked_call(void *func, ...);
 
-/* Call the function */
-#if ARCH_X86_64 && HAVE_YASM
+#if ARCH_X86_64
 /* Evil hack: detect incorrect assumptions that 32-bit ints are zero-extended to 64-bit.
  * This is done by clobbering the stack with junk around the stack pointer and calling the
- * assembly function through x264_checkasm_call with added dummy arguments which forces all
+ * assembly function through checked_call() with added dummy arguments which forces all
  * real arguments to be passed on the stack and not in registers. For 32-bit arguments the
  * upper half of the 64-bit register locations on the stack will now contain junk which will
  * cause misbehaving functions to either produce incorrect output or segfault. Note that
@@ -77,14 +77,20 @@ intptr_t checkasm_checked_call(intptr_t (*func)(), ...);
  * and false negatives is theoretically possible, but there can never be any false positives.
  */
 void checkasm_stack_clobber(uint64_t clobber, ...);
+#define declare_new(ret, ...) ret (*checked_call)(void *, int, int, int, int, int, __VA_ARGS__)\
+                              = (void *)checkasm_checked_call;
 #define CLOB (UINT64_C(0xdeadbeefdeadbeef))
 #define call_new(...) (checkasm_stack_clobber(CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,\
                                               CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB,CLOB),\
-                      checkasm_checked_call(func_new, 0, 0, 0, 0, 0, __VA_ARGS__))
-#elif ARCH_X86_32 && HAVE_YASM
-#define call_new(...) checkasm_checked_call(func_new, __VA_ARGS__)
+                      checked_call(func_new, 0, 0, 0, 0, 0, __VA_ARGS__))
+#elif ARCH_X86_32
+#define declare_new(ret, ...) ret (*checked_call)(void *, __VA_ARGS__) = (void *)checkasm_checked_call;
+#define call_new(...) checked_call(func_new, __VA_ARGS__)
+#endif
 #else
-#define call_new(...) func_new(__VA_ARGS__)
+#define declare_new(ret, ...)
+/* Call the function */
+#define call_new(...) ((func_type *)func_new)(__VA_ARGS__)
 #endif
 
 /* Benchmark the function */
@@ -92,7 +98,7 @@ void checkasm_stack_clobber(uint64_t clobber, ...);
 #define bench_new(...)\
     do {\
         if (checkasm_bench_func()) {\
-            intptr_t (*tfunc)() = func_new;\
+            func_type *tfunc = func_new;\
             uint64_t tsum = 0;\
             int ti, tcount = 0;\
             for (ti = 0; ti < BENCH_RUNS; ti++) {\
diff --git a/tests/checkasm/h264pred.c b/tests/checkasm/h264pred.c
index 08f23e61b210705101a0bedd2782ea17bc8d440d..a1ee720fae0616545364c16612db5cef75f26c70 100644
--- a/tests/checkasm/h264pred.c
+++ b/tests/checkasm/h264pred.c
@@ -144,14 +144,16 @@ static void check_pred4x4(H264PredContext *h, uint8_t *buf0, uint8_t *buf1,
     if (chroma_format == 1) {
         uint8_t *topright = buf0 + 2*16;
         int pred_mode;
+        declare_func(void, uint8_t *src, const uint8_t *topright, ptrdiff_t stride);
+
         for (pred_mode = 0; pred_mode < 15; pred_mode++) {
             if (check_pred_func(h->pred4x4[pred_mode], "4x4", pred4x4_modes[codec][pred_mode])) {
                 randomize_buffers();
-                call_ref(src0, topright, (ptrdiff_t)12*SIZEOF_PIXEL);
-                call_new(src1, topright, (ptrdiff_t)12*SIZEOF_PIXEL);
+                call_ref(src0, topright, 12*SIZEOF_PIXEL);
+                call_new(src1, topright, 12*SIZEOF_PIXEL);
                 if (memcmp(buf0, buf1, BUF_SIZE))
                     fail();
-                bench_new(src1, topright, (ptrdiff_t)12*SIZEOF_PIXEL);
+                bench_new(src1, topright, 12*SIZEOF_PIXEL);
             }
         }
     }
@@ -161,15 +163,17 @@ static void check_pred8x8(H264PredContext *h, uint8_t *buf0, uint8_t *buf1,
                           int codec, int chroma_format, int bit_depth)
 {
     int pred_mode;
+    declare_func(void, uint8_t *src, ptrdiff_t stride);
+
     for (pred_mode = 0; pred_mode < 11; pred_mode++) {
         if (check_pred_func(h->pred8x8[pred_mode], (chroma_format == 2) ? "8x16" : "8x8",
                             pred8x8_modes[codec][pred_mode])) {
             randomize_buffers();
-            call_ref(src0, (ptrdiff_t)24*SIZEOF_PIXEL);
-            call_new(src1, (ptrdiff_t)24*SIZEOF_PIXEL);
+            call_ref(src0, 24*SIZEOF_PIXEL);
+            call_new(src1, 24*SIZEOF_PIXEL);
             if (memcmp(buf0, buf1, BUF_SIZE))
                 fail();
-            bench_new(src1, (ptrdiff_t)24*SIZEOF_PIXEL);
+            bench_new(src1, 24*SIZEOF_PIXEL);
         }
     }
 }
@@ -179,14 +183,16 @@ static void check_pred16x16(H264PredContext *h, uint8_t *buf0, uint8_t *buf1,
 {
     if (chroma_format == 1) {
         int pred_mode;
+        declare_func(void, uint8_t *src, ptrdiff_t stride);
+
         for (pred_mode = 0; pred_mode < 9; pred_mode++) {
             if (check_pred_func(h->pred16x16[pred_mode], "16x16", pred16x16_modes[codec][pred_mode])) {
                 randomize_buffers();
-                call_ref(src0, (ptrdiff_t)48);
-                call_new(src1, (ptrdiff_t)48);
+                call_ref(src0, 48);
+                call_new(src1, 48);
                 if (memcmp(buf0, buf1, BUF_SIZE))
                     fail();
-                bench_new(src1, (ptrdiff_t)48);
+                bench_new(src1, 48);
             }
         }
     }
@@ -197,6 +203,8 @@ static void check_pred8x8l(H264PredContext *h, uint8_t *buf0, uint8_t *buf1,
 {
     if (chroma_format == 1 && codec_ids[codec] == AV_CODEC_ID_H264) {
         int pred_mode;
+        declare_func(void, uint8_t *src, int topleft, int topright, ptrdiff_t stride);
+
         for (pred_mode = 0; pred_mode < 12; pred_mode++) {
             if (check_pred_func(h->pred8x8l[pred_mode], "8x8l", pred4x4_modes[codec][pred_mode])) {
                 int neighbors;
@@ -208,11 +216,11 @@ static void check_pred8x8l(H264PredContext *h, uint8_t *buf0, uint8_t *buf1,
                         continue; /* Those aren't allowed according to the spec */
 
                     randomize_buffers();
-                    call_ref(src0, has_topleft, has_topright, (ptrdiff_t)24*SIZEOF_PIXEL);
-                    call_new(src1, has_topleft, has_topright, (ptrdiff_t)24*SIZEOF_PIXEL);
+                    call_ref(src0, has_topleft, has_topright, 24*SIZEOF_PIXEL);
+                    call_new(src1, has_topleft, has_topright, 24*SIZEOF_PIXEL);
                     if (memcmp(buf0, buf1, BUF_SIZE))
                         fail();
-                    bench_new(src1, has_topleft, has_topright, (ptrdiff_t)24*SIZEOF_PIXEL);
+                    bench_new(src1, has_topleft, has_topright, 24*SIZEOF_PIXEL);
                 }
             }
         }
diff --git a/tests/checkasm/h264qpel.c b/tests/checkasm/h264qpel.c
index f734945729fa3d611a6f053e1168e9e0dab53ae9..27bcc97cfc58967fffa88bfd98ce88426fe4b240 100644
--- a/tests/checkasm/h264qpel.c
+++ b/tests/checkasm/h264qpel.c
@@ -55,6 +55,7 @@ void checkasm_check_h264qpel(void)
     LOCAL_ALIGNED_16(uint8_t, dst1, [BUF_SIZE]);
     H264QpelContext h;
     int op, bit_depth, i, j;
+    declare_func(void, uint8_t *dst, const uint8_t *src, ptrdiff_t stride);
 
     for (op = 0; op < 2; op++) {
         qpel_mc_func (*tab)[16] = op ? h.avg_h264_qpel_pixels_tab : h.put_h264_qpel_pixels_tab;
@@ -67,11 +68,11 @@ void checkasm_check_h264qpel(void)
                 for (j = 0; j < 16; j++)
                     if (check_func(tab[i][j], "%s_h264_qpel_%d_mc%d%d_%d", op_name, size, j & 3, j >> 2, bit_depth)) {
                         randomize_buffers();
-                        call_ref(dst0, src0, (ptrdiff_t)size * SIZEOF_PIXEL);
-                        call_new(dst1, src1, (ptrdiff_t)size * SIZEOF_PIXEL);
+                        call_ref(dst0, src0, size * SIZEOF_PIXEL);
+                        call_new(dst1, src1, size * SIZEOF_PIXEL);
                         if (memcmp(buf0, buf1, BUF_SIZE) || memcmp(dst0, dst1, BUF_SIZE))
                             fail();
-                        bench_new(dst1, src1, (ptrdiff_t)size * SIZEOF_PIXEL);
+                        bench_new(dst1, src1, size * SIZEOF_PIXEL);
                     }
             }
         }
diff --git a/tests/checkasm/x86/checkasm.asm b/tests/checkasm/x86/checkasm.asm
index 20d11bc5c85290fa7581e84b1bb16fa67395930e..4948fc9e264d4b1852ad241528382109e8d0393a 100644
--- a/tests/checkasm/x86/checkasm.asm
+++ b/tests/checkasm/x86/checkasm.asm
@@ -82,7 +82,7 @@ cglobal stack_clobber, 1,2
 %endif
 
 ;-----------------------------------------------------------------------------
-; intptr_t checkasm_checked_call(intptr_t (*func)(), ...)
+; void checkasm_checked_call(void *func, ...)
 ;-----------------------------------------------------------------------------
 INIT_XMM
 cglobal checked_call, 2,15,16,max_args*8+8
@@ -167,7 +167,7 @@ cglobal checked_call, 2,15,16,max_args*8+8
 %define n6 dword 0x33627ba7
 
 ;-----------------------------------------------------------------------------
-; intptr_t checkasm_checked_call(intptr_t (*func)(), ...)
+; void checkasm_checked_call(void *func, ...)
 ;-----------------------------------------------------------------------------
 cglobal checked_call, 1,7
     mov  r3, n3