py: Fix undefined left shift operations.

jepler · dpgeorge · commit 2c8ccd3ee894 · 2025-06-16T23:27:50.000+10:00
By ensuring the value to be shifted is an unsigned of the appropriate type.

This fixes several runtime diagnostics such as:

    ../../py/binary.c:199:28: runtime error:
     left shift of 32768 by 16 places
     cannot be represented in type 'int'

Signed-off-by: Jeff Epler &lt;jepler@gmail.com&gt;
diff --git a/py/binary.c b/py/binary.c
@@ -196,7 +196,7 @@ static float mp_decode_half_float(uint16_t hf) {
         ++e;
     }
 
-    fpu.i = ((hf & 0x8000) << 16) | (e << 23) | (m << 13);
+    fpu.i = ((hf & 0x8000u) << 16) | (e << 23) | (m << 13);
     return fpu.f;
 }
 
diff --git a/py/persistentcode.c b/py/persistentcode.c
@@ -759,7 +759,7 @@ static void bit_vector_clear(bit_vector_t *self) {
 static bool bit_vector_is_set(bit_vector_t *self, size_t index) {
     const size_t bits_size = sizeof(*self->bits) * MP_BITS_PER_BYTE;
     return index / bits_size < self->alloc
-           && (self->bits[index / bits_size] & (1 << (index % bits_size))) != 0;
+           && (self->bits[index / bits_size] & ((uintptr_t)1 << (index % bits_size))) != 0;
 }
 
 static void bit_vector_set(bit_vector_t *self, size_t index) {
@@ -770,7 +770,7 @@ static void bit_vector_set(bit_vector_t *self, size_t index) {
         self->bits = m_renew(uintptr_t, self->bits, self->alloc, new_alloc);
         self->alloc = new_alloc;
     }
-    self->bits[index / bits_size] |= 1 << (index % bits_size);
+    self->bits[index / bits_size] |= (uintptr_t)1 << (index % bits_size);
 }
 
 typedef struct _mp_opcode_t {

Original file line number	Diff line number	Diff line change
`@@ -196,7 +196,7 @@ static float mp_decode_half_float(uint16_t hf) {`
`196`	`196`	`++e;`
`197`	`197`	`}`
`198`	`198`
`199`		`- fpu.i = ((hf & 0x8000) << 16) \| (e << 23) \| (m << 13);`
	`199`	`+ fpu.i = ((hf & 0x8000u) << 16) \| (e << 23) \| (m << 13);`
`200`	`200`	`return fpu.f;`
`201`	`201`	`}`
`202`	`202`
Original file line number	Diff line number	Diff line change
`@@ -759,7 +759,7 @@ static void bit_vector_clear(bit_vector_t *self) {`
`759`	`759`	`static bool bit_vector_is_set(bit_vector_t *self, size_t index) {`
`760`	`760`	`const size_t bits_size = sizeof(self->bits) MP_BITS_PER_BYTE;`
`761`	`761`	`return index / bits_size < self->alloc`
`762`		`- && (self->bits[index / bits_size] & (1 << (index % bits_size))) != 0;`
	`762`	`+ && (self->bits[index / bits_size] & ((uintptr_t)1 << (index % bits_size))) != 0;`
`763`	`763`	`}`
`764`	`764`
`765`	`765`	`static void bit_vector_set(bit_vector_t *self, size_t index) {`
`@@ -770,7 +770,7 @@ static void bit_vector_set(bit_vector_t *self, size_t index) {`
`770`	`770`	`self->bits = m_renew(uintptr_t, self->bits, self->alloc, new_alloc);`
`771`	`771`	`self->alloc = new_alloc;`
`772`	`772`	`}`
`773`		`- self->bits[index / bits_size] \|= 1 << (index % bits_size);`
	`773`	`+ self->bits[index / bits_size] \|= (uintptr_t)1 << (index % bits_size);`
`774`	`774`	`}`
`775`	`775`
`776`	`776`	`typedef struct _mp_opcode_t {`