bpo-31338 (#3374)
* Add Py_UNREACHABLE() as an alias to abort().
* Use Py_UNREACHABLE() instead of assert(0)
* Convert more unreachable code to use Py_UNREACHABLE()
* Document Py_UNREACHABLE() and a few other macros.
diff --git a/Objects/abstract.c b/Objects/abstract.c
index 998bcb1..38484b7 100644
--- a/Objects/abstract.c
+++ b/Objects/abstract.c
@@ -1984,7 +1984,7 @@
goto Done;
default:
- assert(!"unknown operation");
+ Py_UNREACHABLE();
}
}
diff --git a/Objects/bytesobject.c b/Objects/bytesobject.c
index d91cb7d..6a4eb67 100644
--- a/Objects/bytesobject.c
+++ b/Objects/bytesobject.c
@@ -868,7 +868,7 @@
switch(c)
{
default:
- assert(0 && "'type' not in [diuoxX]");
+ Py_UNREACHABLE();
case 'd':
case 'i':
case 'u':
diff --git a/Objects/dictobject.c b/Objects/dictobject.c
index 81c7f7f..6ba2cc9 100644
--- a/Objects/dictobject.c
+++ b/Objects/dictobject.c
@@ -643,8 +643,7 @@
perturb >>= PERTURB_SHIFT;
i = mask & (i*5 + perturb + 1);
}
- assert(0); /* NOT REACHED */
- return DKIX_ERROR;
+ Py_UNREACHABLE();
}
/*
@@ -723,8 +722,7 @@
perturb >>= PERTURB_SHIFT;
i = (i*5 + perturb + 1) & mask;
}
- assert(0); /* NOT REACHED */
- return 0;
+ Py_UNREACHABLE();
}
/* Specialized version for string-only keys */
@@ -766,9 +764,7 @@
perturb >>= PERTURB_SHIFT;
i = mask & (i*5 + perturb + 1);
}
-
- assert(0); /* NOT REACHED */
- return 0;
+ Py_UNREACHABLE();
}
/* Faster version of lookdict_unicode when it is known that no <dummy> keys
@@ -810,8 +806,7 @@
perturb >>= PERTURB_SHIFT;
i = mask & (i*5 + perturb + 1);
}
- assert(0); /* NOT REACHED */
- return 0;
+ Py_UNREACHABLE();
}
/* Version of lookdict for split tables.
@@ -856,8 +851,7 @@
perturb >>= PERTURB_SHIFT;
i = mask & (i*5 + perturb + 1);
}
- assert(0); /* NOT REACHED */
- return 0;
+ Py_UNREACHABLE();
}
int
@@ -3603,7 +3597,7 @@
else if (Py_TYPE(di) == &PyDictIterValue_Type)
element = dictiter_iternextvalue(&tmp);
else
- assert(0);
+ Py_UNREACHABLE();
if (element) {
if (PyList_Append(list, element)) {
Py_DECREF(element);
diff --git a/Objects/longobject.c b/Objects/longobject.c
index 4862b76..3b07585 100644
--- a/Objects/longobject.c
+++ b/Objects/longobject.c
@@ -1806,8 +1806,7 @@
bits = 1;
break;
default:
- assert(0); /* shouldn't ever get here */
- bits = 0; /* to silence gcc warning */
+ Py_UNREACHABLE();
}
/* Compute exact length 'sz' of output string. */
@@ -2169,8 +2168,8 @@
}
}
if (str[0] == '_') {
- /* May not start with underscores. */
- goto onError;
+ /* May not start with underscores. */
+ goto onError;
}
start = str;
diff --git a/Objects/stringlib/eq.h b/Objects/stringlib/eq.h
index f8fd384..ff22f91 100644
--- a/Objects/stringlib/eq.h
+++ b/Objects/stringlib/eq.h
@@ -10,8 +10,7 @@
PyUnicodeObject *b = (PyUnicodeObject *)bb;
if (PyUnicode_READY(a) == -1 || PyUnicode_READY(b) == -1) {
- assert(0 && "unicode_eq ready fail");
- return 0;
+ Py_UNREACHABLE();
}
if (PyUnicode_GET_LENGTH(a) != PyUnicode_GET_LENGTH(b))
diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index c4d93fc..bb1c083 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -768,7 +768,7 @@
BLOOM_UPDATE(Py_UCS4, mask, ptr, len);
break;
default:
- assert(0);
+ Py_UNREACHABLE();
}
return mask;
@@ -869,8 +869,7 @@
else
return ucs4lib_rfind_char((Py_UCS4 *) s, size, ch);
default:
- assert(0);
- return -1;
+ Py_UNREACHABLE();
}
}
@@ -1520,8 +1519,7 @@
);
}
else {
- assert(0);
- return -1;
+ Py_UNREACHABLE();
}
}
else {
@@ -2079,7 +2077,7 @@
#endif
break;
default:
- assert(0 && "Impossible state");
+ Py_UNREACHABLE();
}
return unicode_result(unicode);
@@ -2172,8 +2170,7 @@
case PyUnicode_4BYTE_KIND:
return 0x10000;
default:
- assert(0 && "invalid kind");
- return MAX_UNICODE;
+ Py_UNREACHABLE();
}
}
@@ -2317,8 +2314,7 @@
case PyUnicode_4BYTE_KIND:
return ucs4lib_find_max_char(startptr, endptr);
default:
- assert(0);
- return 0;
+ Py_UNREACHABLE();
}
}
@@ -4068,7 +4064,7 @@
*w = *four_bytes;
if (w > wchar_end) {
- assert(0 && "Miscalculated string end");
+ Py_UNREACHABLE();
}
}
*w = 0;
@@ -4120,7 +4116,7 @@
#endif
}
else {
- assert(0 && "This should never happen.");
+ Py_UNREACHABLE();
}
}
}
@@ -5134,7 +5130,7 @@
#endif
if (ch > 0xFF) {
#if SIZEOF_WCHAR_T == 4
- assert(0);
+ Py_UNREACHABLE();
#else
assert(ch > 0xFFFF && ch <= MAX_UNICODE);
/* compute and append the two surrogates: */
@@ -5187,7 +5183,7 @@
switch (kind) {
default:
- assert(0);
+ Py_UNREACHABLE();
case PyUnicode_1BYTE_KIND:
/* the string cannot be ASCII, or PyUnicode_UTF8() would be set */
assert(!PyUnicode_IS_ASCII(unicode));
@@ -9294,7 +9290,7 @@
result = ucs4lib_find_slice(buf1, len1, buf2, len2, start, end);
break;
default:
- assert(0); result = -2;
+ Py_UNREACHABLE();
}
}
else {
@@ -9312,7 +9308,7 @@
result = ucs4lib_rfind_slice(buf1, len1, buf2, len2, start, end);
break;
default:
- assert(0); result = -2;
+ Py_UNREACHABLE();
}
}
@@ -9386,8 +9382,7 @@
(Py_UCS4 *) thousands_sep_data, thousands_sep_len);
break;
default:
- assert(0);
- return -1;
+ Py_UNREACHABLE();
}
if (unicode != NULL && thousands_sep_kind != kind) {
if (thousands_sep_kind < kind)
@@ -9465,7 +9460,7 @@
);
break;
default:
- assert(0); result = 0;
+ Py_UNREACHABLE();
}
if (kind2 != kind1)
@@ -9881,8 +9876,7 @@
memcpy(outdata, tmp, sizeof(Py_UCS4) * newlength);
break;
default:
- assert(0);
- break;
+ Py_UNREACHABLE();
}
leave:
PyMem_FREE(tmp);
@@ -10105,7 +10099,7 @@
for (; i_ < (length); ++i_, ++to_) *to_ = (value); \
break; \
} \
- default: assert(0); \
+ default: Py_UNREACHABLE(); \
} \
} while (0)
@@ -10229,8 +10223,7 @@
PyUnicode_GET_LENGTH(string), keepends);
break;
default:
- assert(0);
- list = 0;
+ Py_UNREACHABLE();
}
return list;
}
@@ -10275,8 +10268,7 @@
PyUnicode_GET_LENGTH(self), maxcount
);
default:
- assert(0);
- return NULL;
+ Py_UNREACHABLE();
}
if (PyUnicode_READY(substring) == -1)
@@ -10367,8 +10359,7 @@
PyUnicode_GET_LENGTH(self), maxcount
);
default:
- assert(0);
- return NULL;
+ Py_UNREACHABLE();
}
if (PyUnicode_READY(substring) == -1)
@@ -10434,8 +10425,7 @@
case PyUnicode_4BYTE_KIND:
return ucs4lib_find(buf1, len1, buf2, len2, offset);
}
- assert(0);
- return -1;
+ Py_UNREACHABLE();
}
static Py_ssize_t
@@ -10453,8 +10443,7 @@
case PyUnicode_4BYTE_KIND:
return ucs4lib_count(sbuf, slen, buf1, len1, maxcount);
}
- assert(0);
- return 0;
+ Py_UNREACHABLE();
}
static void
@@ -10909,7 +10898,7 @@
COMPARE(Py_UCS1, Py_UCS4);
break;
default:
- assert(0);
+ Py_UNREACHABLE();
}
break;
}
@@ -10928,7 +10917,7 @@
COMPARE(Py_UCS2, Py_UCS4);
break;
default:
- assert(0);
+ Py_UNREACHABLE();
}
break;
}
@@ -10956,12 +10945,12 @@
break;
}
default:
- assert(0);
+ Py_UNREACHABLE();
}
break;
}
default:
- assert(0);
+ Py_UNREACHABLE();
}
if (len1 == len2)
@@ -11285,8 +11274,7 @@
result = ucs4lib_find(buf1, len1, buf2, len2, 0) != -1;
break;
default:
- result = -1;
- assert(0);
+ Py_UNREACHABLE();
}
if (kind2 != kind1)
@@ -11511,7 +11499,7 @@
);
break;
default:
- assert(0); iresult = 0;
+ Py_UNREACHABLE();
}
result = PyLong_FromSsize_t(iresult);
@@ -12985,8 +12973,7 @@
out = ucs4lib_partition(str_obj, buf1, len1, sep_obj, buf2, len2);
break;
default:
- assert(0);
- out = 0;
+ Py_UNREACHABLE();
}
if (kind2 != kind1)
@@ -13043,8 +13030,7 @@
out = ucs4lib_rpartition(str_obj, buf1, len1, sep_obj, buf2, len2);
break;
default:
- assert(0);
- out = 0;
+ Py_UNREACHABLE();
}
if (kind2 != kind1)
@@ -13627,8 +13613,7 @@
case PyUnicode_2BYTE_KIND: maxchar = 0xffff; break;
case PyUnicode_4BYTE_KIND: maxchar = 0x10ffff; break;
default:
- assert(0 && "invalid kind");
- return -1;
+ Py_UNREACHABLE();
}
return _PyUnicodeWriter_PrepareInternal(writer, 0, maxchar);
@@ -13770,7 +13755,7 @@
break;
}
default:
- assert(0);
+ Py_UNREACHABLE();
}
writer->pos += len;
@@ -14204,7 +14189,7 @@
switch (type) {
default:
- assert(!"'type' not in [diuoxX]");
+ Py_UNREACHABLE();
case 'd':
case 'i':
case 'u':
@@ -14362,7 +14347,7 @@
switch(type)
{
default:
- assert(0 && "'type' not in [diuoxX]");
+ Py_UNREACHABLE();
case 'd':
case 'i':
case 'u':
@@ -15373,8 +15358,7 @@
for (i = 0; i < n; i++) {
s = PyList_GET_ITEM(keys, i);
if (PyUnicode_READY(s) == -1) {
- assert(0 && "could not ready string");
- fprintf(stderr, "could not ready string\n");
+ Py_UNREACHABLE();
}
switch (PyUnicode_CHECK_INTERNED(s)) {
case SSTATE_NOT_INTERNED: