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| author | Yoctopuce dev <dev@yoctopuce.com> | 2025-06-19 15:47:13 +0200 |
|---|---|---|
| committer | Damien George <damien@micropython.org> | 2025-06-24 00:30:08 +1000 |
| commit | e57aa7e70a326659529d02891abb9a57b055fc0c (patch) | |
| tree | 699f53a51d4defd79c0f16bad3b231cc515f0b36 | |
| parent | 66c01480226aaf880a9d6e88340772bd53bc0421 (diff) | |
| download | micropython-master.tar.gz micropython-master.zip | |
CPython math.nan is positive with regards to copysign. The signaling bit
(aka sign flag) was incorrectly set.
In addition, REPR_C and REPR_D should only use the _true_ nan to prevent
system crash in case of hand-crafted floats. For instance, with REPR_C,
any nan-like float following the pattern
`01111111 1xxxxxxx xxxxxxxx xxxxx1xx` would be switched to an immediate
object or a qstr string. When the qstr index is too large, this would
cause a crash.
This commit fixes the issue, and adds the relevant test cases.
Signed-off-by: Yoctopuce dev <dev@yoctopuce.com>
| -rw-r--r-- | ports/windows/mpconfigport.h | 5 | ||||
| -rw-r--r-- | py/modmath.c | 5 | ||||
| -rw-r--r-- | py/obj.h | 20 | ||||
| -rw-r--r-- | tests/float/float_array.py | 8 | ||||
| -rw-r--r-- | tests/float/math_constants_extra.py | 3 |
5 files changed, 37 insertions, 4 deletions
diff --git a/ports/windows/mpconfigport.h b/ports/windows/mpconfigport.h index 6e32d5fe5e..4e140d5edb 100644 --- a/ports/windows/mpconfigport.h +++ b/ports/windows/mpconfigport.h @@ -266,6 +266,11 @@ typedef long mp_off_t; #endif #endif +// VC++ 2017 fixes +#if (_MSC_VER < 1920) +#define MICROPY_PY_MATH_COPYSIGN_FIX_NAN (1) +#endif + // CL specific definitions #ifndef __cplusplus diff --git a/py/modmath.c b/py/modmath.c index b792d8581d..919a8ccd9d 100644 --- a/py/modmath.c +++ b/py/modmath.c @@ -161,6 +161,11 @@ MATH_FUN_2(atan2, atan2) MATH_FUN_1_TO_INT(ceil, ceil) // copysign(x, y) static mp_float_t MICROPY_FLOAT_C_FUN(copysign_func)(mp_float_t x, mp_float_t y) { + #if MICROPY_PY_MATH_COPYSIGN_FIX_NAN + if (isnan(y)) { + y = 0.0; + } + #endif return MICROPY_FLOAT_C_FUN(copysign)(x, y); } MATH_FUN_2(copysign, copysign_func) @@ -184,13 +184,15 @@ static inline bool mp_obj_is_small_int(mp_const_obj_t o) { #define MP_OBJ_NEW_SMALL_INT(small_int) ((mp_obj_t)((((mp_uint_t)(small_int)) << 1) | 1)) #if MICROPY_PY_BUILTINS_FLOAT -#define MP_OBJ_NEW_CONST_FLOAT(f) MP_ROM_PTR((mp_obj_t)((((((uint64_t)f) & ~3) | 2) + 0x80800000) & 0xffffffff)) +#include <math.h> +// note: MP_OBJ_NEW_CONST_FLOAT should be a MP_ROM_PTR but that macro isn't available yet +#define MP_OBJ_NEW_CONST_FLOAT(f) ((mp_obj_t)((((((uint64_t)f) & ~3) | 2) + 0x80800000) & 0xffffffff)) #define mp_const_float_e MP_OBJ_NEW_CONST_FLOAT(0x402df854) #define mp_const_float_pi MP_OBJ_NEW_CONST_FLOAT(0x40490fdb) +#define mp_const_float_nan MP_OBJ_NEW_CONST_FLOAT(0x7fc00000) #if MICROPY_PY_MATH_CONSTANTS #define mp_const_float_tau MP_OBJ_NEW_CONST_FLOAT(0x40c90fdb) #define mp_const_float_inf MP_OBJ_NEW_CONST_FLOAT(0x7f800000) -#define mp_const_float_nan MP_OBJ_NEW_CONST_FLOAT(0xffc00000) #endif static inline bool mp_obj_is_float(mp_const_obj_t o) { @@ -207,6 +209,10 @@ static inline mp_float_t mp_obj_float_get(mp_const_obj_t o) { return num.f; } static inline mp_obj_t mp_obj_new_float(mp_float_t f) { + if (isnan(f)) { + // prevent creation of bad nanboxed pointers via array.array or struct + return mp_const_float_nan; + } union { mp_float_t f; mp_uint_t u; @@ -257,12 +263,13 @@ static inline bool mp_obj_is_immediate_obj(mp_const_obj_t o) { #error MICROPY_OBJ_REPR_D requires MICROPY_FLOAT_IMPL_DOUBLE #endif +#include <math.h> #define mp_const_float_e {((mp_obj_t)((uint64_t)0x4005bf0a8b145769 + 0x8004000000000000))} #define mp_const_float_pi {((mp_obj_t)((uint64_t)0x400921fb54442d18 + 0x8004000000000000))} +#define mp_const_float_nan {((mp_obj_t)((uint64_t)0x7ff8000000000000 + 0x8004000000000000))} #if MICROPY_PY_MATH_CONSTANTS #define mp_const_float_tau {((mp_obj_t)((uint64_t)0x401921fb54442d18 + 0x8004000000000000))} #define mp_const_float_inf {((mp_obj_t)((uint64_t)0x7ff0000000000000 + 0x8004000000000000))} -#define mp_const_float_nan {((mp_obj_t)((uint64_t)0xfff8000000000000 + 0x8004000000000000))} #endif static inline bool mp_obj_is_float(mp_const_obj_t o) { @@ -276,6 +283,13 @@ static inline mp_float_t mp_obj_float_get(mp_const_obj_t o) { return num.f; } static inline mp_obj_t mp_obj_new_float(mp_float_t f) { + if (isnan(f)) { + // prevent creation of bad nanboxed pointers via array.array or struct + struct { + uint64_t r; + } num = mp_const_float_nan; + return num.r; + } union { mp_float_t f; uint64_t r; diff --git a/tests/float/float_array.py b/tests/float/float_array.py index 3d128da838..cfff3b220c 100644 --- a/tests/float/float_array.py +++ b/tests/float/float_array.py @@ -19,4 +19,10 @@ def test(a): test(array("f")) test(array("d")) -print("{:.4f}".format(array("f", bytes(array("I", [0x3DCCCCCC])))[0])) +# hand-crafted floats, including non-standard nan +for float_hex in (0x3DCCCCCC, 0x7F800024, 0x7FC00004): + f = array("f", bytes(array("I", [float_hex])))[0] + if type(f) is float: + print("{:.4e}".format(f)) + else: + print(f) diff --git a/tests/float/math_constants_extra.py b/tests/float/math_constants_extra.py index dea49aef5a..756cb45803 100644 --- a/tests/float/math_constants_extra.py +++ b/tests/float/math_constants_extra.py @@ -9,9 +9,12 @@ except (ImportError, AttributeError): raise SystemExit print(math.tau == 2.0 * math.pi) +print(math.copysign(1.0, math.tau)) print(math.inf == float("inf")) print(-math.inf == -float("inf")) +print(math.copysign(1.0, math.inf)) print(isnan(math.nan)) print(isnan(-math.nan)) +print(math.copysign(1.0, math.nan)) |