diff --git a/src/rp2040/pico_platform/include/pico/platform.h b/src/rp2040/pico_platform/include/pico/platform.h
index 437ff31f4..8f746713d 100644
--- a/src/rp2040/pico_platform/include/pico/platform.h
+++ b/src/rp2040/pico_platform/include/pico/platform.h
@@ -183,9 +183,7 @@ return a;
  * \param b the second operand
  * \return a * b
  */
-#define __fast_mul(a, b) __builtin_choose_expr(__builtin_constant_p(b) && !__builtin_constant_p(a), \
-    (__builtin_popcount(b) >= 2 ? __mul_instruction(a,b) : (a)*(b)), \
-    (a)*(b))
+#define __fast_mul(a, b) (__builtin_constant_p(b) && !__builtin_constant_p(a) && __builtin_popcount(b) >= 2 ? __mul_instruction(a,b) : (a)*(b))
 
 #ifdef __cplusplus
 }
diff --git a/src/rp2350/pico_platform/include/pico/platform.h b/src/rp2350/pico_platform/include/pico/platform.h
index 571efd8b8..67cb80ebc 100644
--- a/src/rp2350/pico_platform/include/pico/platform.h
+++ b/src/rp2350/pico_platform/include/pico/platform.h
@@ -244,9 +244,7 @@ __force_inline static int32_t __mul_instruction(int32_t a, int32_t b) {
  * \param b the second operand
  * \return a * b
  */
-#define __fast_mul(a, b) __builtin_choose_expr(__builtin_constant_p(b) && !__builtin_constant_p(a), \
-    (__builtin_popcount(b) >= 2 ? __mul_instruction(a,b) : (a)*(b)), \
-    (a)*(b))
+#define __fast_mul(a, b) (__builtin_constant_p(b) && !__builtin_constant_p(a) && __builtin_popcount(b) >= 2 ? __mul_instruction(a,b) : (a)*(b))
 
 #ifdef __cplusplus
 }
diff --git a/src/rp2_common/pico_float/include/pico/float.h b/src/rp2_common/pico_float/include/pico/float.h
index 958a14ad0..bf2ece7a8 100644
--- a/src/rp2_common/pico_float/include/pico/float.h
+++ b/src/rp2_common/pico_float/include/pico/float.h
@@ -357,8 +357,8 @@ uint64_t float2ufix64(float f, int e);
 // or call the original function
 #if PICO_FLOAT_HAS_FIX32_TO_FLOAT_CONVERSIONS
 // a bit of a hack to inline VFP fixed-point conversion when exponent is constant and in range 1-32
-#define fix2float(m, e) __builtin_choose_expr(__builtin_constant_p(e), (e) >= 1 && (e) <= 32 ? _fix2float_inline(m, e) : fix2 ## float(m, e), fix2 ## float(m, e))
-#define ufix2float(m, e) __builtin_choose_expr(__builtin_constant_p(e), (e) >= 1 && (e) <= 32 ? _ufix2float_inline(m, e) : ufix2 ## float(m, e), ufix2 ## float(m, e))
+#define fix2float(m, e) (__builtin_constant_p(e) && (e) >= 1 && (e) <= 32 ? _fix2float_inline(m, e) : fix2 ## float(m, e))
+#define ufix2float(m, e) (__builtin_constant_p(e) && (e) >= 1 && (e) <= 32 ? _ufix2float_inline(m, e) : ufix2 ## float(m, e))
 
 #define _fix2float_inline(m, e) ({ \
     int32_t _m = m; \
@@ -385,8 +385,8 @@ uint64_t float2ufix64(float f, int e);
 
 #endif
 #if PICO_FLOAT_HAS_FLOAT_TO_FIX32_Z_CONVERSIONS
-#define float2fix_z(f, e) __builtin_choose_expr(__builtin_constant_p(e), (e) >= 1 && (e) <= 32 ? _float2fix_z_inline(f, e) : float2 ## fix_z(f, e), float2 ## fix_z(f, e))
-#define float2ufix_z(f, e) __builtin_choose_expr(__builtin_constant_p(e), (e) >= 1 && (e) <= 32 ? _float2ufix_z_inline(f, e) : float2 ## ufix_z(f, e), float2 ## ufix_z(f, e))
+#define float2fix_z(f, e) (__builtin_constant_p(e) && (e) >= 1 && (e) <= 32 ? _float2fix_z_inline(f, e) : float2 ## fix_z(f, e))
+#define float2ufix_z(f, e) (__builtin_constant_p(e) && (e) >= 1 && (e) <= 32 ? _float2ufix_z_inline(f, e) : float2 ## ufix_z(f, e))
 
 #define _float2fix_z_inline(f, e) ({ \
     int32_t _m; \
@@ -413,8 +413,8 @@ uint64_t float2ufix64(float f, int e);
 
 #endif
 #if PICO_FLOAT_HAS_FLOAT_TO_FIX32_M_CONVERSIONS
-#define float2fix(f, e) __builtin_choose_expr(__builtin_constant_p(e), (e) >= 1 && (e) <= 32 ? _float2fix_inline(f, e) : float2 ## fix(f, e), float2 ## fix(f, e))
-#define float2ufix(f, e) __builtin_choose_expr(__builtin_constant_p(e), (e) >= 1 && (e) <= 32 ? _float2ufix_inline(f, e) : float2 ## ufix(f, e), float2 ## ufix(f, e))
+#define float2fix(f, e) (__builtin_constant_p(e) && (e) >= 1 && (e) <= 32 ? _float2fix_inline(f, e) : float2 ## fix(f, e))
+#define float2ufix(f, e) (__builtin_constant_p(e) && (e) >= 1 && (e) <= 32 ? _float2ufix_inline(f, e) : float2 ## ufix(f, e))
 
 #define _float2fix_inline(f, e) ({ \
     union { float _f; int32_t _i; } _u; \
diff --git a/test/kitchen_sink/kitchen_sink.c b/test/kitchen_sink/kitchen_sink.c
index 81b9fee30..1faf7fe38 100644
--- a/test/kitchen_sink/kitchen_sink.c
+++ b/test/kitchen_sink/kitchen_sink.c
@@ -63,6 +63,42 @@ float __attribute__((noinline)) foox(float x, float b) {
     return x * b;
 }
 
+uint __noinline const_funcs_returning_int(__unused float x, int n) {
+    return __fast_mul(n, 7)
+#if PICO_FLOAT_HAS_FLOAT_TO_FIX32_M_CONVERSIONS
+           + float2fix(x, 7)
+           + float2ufix(x, 7)
+#endif
+#if PICO_FLOAT_HAS_FLOAT_TO_FIX32_Z_CONVERSIONS
+           + float2fix_z(x, 7)
+           + float2ufix_z(x, 7)
+#endif
+        ;
+}
+
+uint __noinline non_const_funcs_returning_int(__unused float x, int n) {
+    return __fast_mul(n, n)
+#if PICO_FLOAT_HAS_FLOAT_TO_FIX32_M_CONVERSIONS
+           + float2fix(x, n)
+           + float2ufix(x, n)
+#endif
+#if PICO_FLOAT_HAS_FLOAT_TO_FIX32_Z_CONVERSIONS
+           + float2fix_z(x, n)
+           + float2ufix_z(x, n)
+#endif
+        ;
+}
+
+#if PICO_FLOAT_HAS_FIX32_TO_FLOAT_CONVERSIONS
+float __noinline const_funcs_returning_float(int n) {
+    return fix2float(n, 7) + ufix2float(n, 7);
+}
+
+float __noinline non_const_funcs_returning_float(int n) {
+    return fix2float(n, n) + ufix2float(n, n);
+}
+#endif
+
 void svc_call(void) {
     puts("PASSED");
     exit(0);
@@ -93,6 +129,10 @@ int main(void) {
     hard_assert(recursive_mutex_try_enter(&recursive_mutex, NULL));
     hard_assert(recursive_mutex_try_enter(&recursive_mutex, NULL));
     printf("%f\n", foox(1.3f, 2.6f));
+    printf("%u %u\n", const_funcs_returning_int(3.7f, 7), non_const_funcs_returning_int(3.7f, 7));
+#if PICO_FLOAT_HAS_FIX32_TO_FLOAT_CONVERSIONS
+    printf("%f %f\n", const_funcs_returning_float(7), non_const_funcs_returning_float(7));
+#endif
 #ifdef EXTRA_DATA_SECTION
     extern uint32_t __extra_end_variable__;
     printf("__extra_end_variable__ = %p\n", (void *)&__extra_end_variable__);