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Differential D21870

[libcxx] [test] Avoid applying unary minus to unsigned integers.
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Authored by STL_MSFT on Jun 29 2016, 4:20 PM.

Details

Reviewers
mclow.lists
EricWF
Summary

Avoid applying unary minus to unsigned integers.

This is confusing because first you have to remember what unsigned negation does, then you have to worry about the usual arithmetic conversions during the comparison. It's simpler to express the most negative values as "blah - 1" expressions, and then the only UAC involved is widening int to long long and that's easy.

Fixes MSVC warning/error C4146 "unary minus operator applied to unsigned type, result still unsigned".

Diff Detail

Event Timeline

STL_MSFT updated this revision to Diff 62302.Jun 29 2016, 4:20 PM
STL_MSFT retitled this revision from to [libcxx] [test] Avoid applying unary minus to unsigned integers..
STL_MSFT updated this object.
STL_MSFT added reviewers: EricWF, mclow.lists.
STL_MSFT added a subscriber: cfe-commits.
EricWF accepted this revision.Jun 29 2016, 9:27 PM
EricWF edited edge metadata.
This revision is now accepted and ready to land.Jun 29 2016, 9:27 PM
EricWF closed this revision.Jun 29 2016, 9:29 PM

r274203.

Revision Contents

PathSize
test/
std/
depr/
depr.c.headers/
8 lines
language.support/
cstdint/
cstdint.syn/
8 lines

Diff 62302

test/std/depr/depr.c.headers/stdint_h.pass.cpp

Show First 20 Lines • Show All 165 Lines • ▼ Show 20 Linesint main()
static_assert(sizeof(uintmax_t) >= sizeof(unsigned long long), static_assert(sizeof(uintmax_t) >= sizeof(unsigned long long),
"sizeof(uintmax_t) >= sizeof(unsigned long long)"); "sizeof(uintmax_t) >= sizeof(unsigned long long)");
static_assert(std::is_unsigned<uintmax_t>::value, static_assert(std::is_unsigned<uintmax_t>::value,
"std::is_unsigned<uintmax_t>::value"); "std::is_unsigned<uintmax_t>::value");
// INTN_MIN // INTN_MIN
static_assert(INT8_MIN == -128, "INT8_MIN == -128"); static_assert(INT8_MIN == -128, "INT8_MIN == -128");
static_assert(INT16_MIN == -32768, "INT16_MIN == -32768"); static_assert(INT16_MIN == -32768, "INT16_MIN == -32768");
static_assert(INT32_MIN == -2147483648U, "INT32_MIN == -2147483648"); static_assert(INT32_MIN == -2147483647 - 1, "INT32_MIN == -2147483648");
static_assert(INT64_MIN == -9223372036854775808ULL, "INT64_MIN == -9223372036854775808LL"); static_assert(INT64_MIN == -9223372036854775807LL - 1, "INT64_MIN == -9223372036854775808LL");
// INTN_MAX // INTN_MAX
static_assert(INT8_MAX == 127, "INT8_MAX == 127"); static_assert(INT8_MAX == 127, "INT8_MAX == 127");
static_assert(INT16_MAX == 32767, "INT16_MAX == 32767"); static_assert(INT16_MAX == 32767, "INT16_MAX == 32767");
static_assert(INT32_MAX == 2147483647, "INT32_MAX == 2147483647"); static_assert(INT32_MAX == 2147483647, "INT32_MAX == 2147483647");
static_assert(INT64_MAX == 9223372036854775807LL, "INT64_MAX == 9223372036854775807LL"); static_assert(INT64_MAX == 9223372036854775807LL, "INT64_MAX == 9223372036854775807LL");
// UINTN_MAX // UINTN_MAX
static_assert(UINT8_MAX == 255, "UINT8_MAX == 255"); static_assert(UINT8_MAX == 255, "UINT8_MAX == 255");
static_assert(UINT16_MAX == 65535, "UINT16_MAX == 65535"); static_assert(UINT16_MAX == 65535, "UINT16_MAX == 65535");
static_assert(UINT32_MAX == 4294967295U, "UINT32_MAX == 4294967295"); static_assert(UINT32_MAX == 4294967295U, "UINT32_MAX == 4294967295");
static_assert(UINT64_MAX == 18446744073709551615ULL, "UINT64_MAX == 18446744073709551615ULL"); static_assert(UINT64_MAX == 18446744073709551615ULL, "UINT64_MAX == 18446744073709551615ULL");
// INT_FASTN_MIN // INT_FASTN_MIN
static_assert(INT_FAST8_MIN <= -128, "INT_FAST8_MIN <= -128"); static_assert(INT_FAST8_MIN <= -128, "INT_FAST8_MIN <= -128");
static_assert(INT_FAST16_MIN <= -32768, "INT_FAST16_MIN <= -32768"); static_assert(INT_FAST16_MIN <= -32768, "INT_FAST16_MIN <= -32768");
static_assert(INT_FAST32_MIN <= -2147483648U, "INT_FAST32_MIN <= -2147483648"); static_assert(INT_FAST32_MIN <= -2147483647 - 1, "INT_FAST32_MIN <= -2147483648");
static_assert(INT_FAST64_MIN <= -9223372036854775808ULL, "INT_FAST64_MIN <= -9223372036854775808LL"); static_assert(INT_FAST64_MIN <= -9223372036854775807LL - 1, "INT_FAST64_MIN <= -9223372036854775808LL");
// INT_FASTN_MAX // INT_FASTN_MAX
static_assert(INT_FAST8_MAX >= 127, "INT_FAST8_MAX >= 127"); static_assert(INT_FAST8_MAX >= 127, "INT_FAST8_MAX >= 127");
static_assert(INT_FAST16_MAX >= 32767, "INT_FAST16_MAX >= 32767"); static_assert(INT_FAST16_MAX >= 32767, "INT_FAST16_MAX >= 32767");
static_assert(INT_FAST32_MAX >= 2147483647, "INT_FAST32_MAX >= 2147483647"); static_assert(INT_FAST32_MAX >= 2147483647, "INT_FAST32_MAX >= 2147483647");
static_assert(INT_FAST64_MAX >= 9223372036854775807LL, "INT_FAST64_MAX >= 9223372036854775807LL"); static_assert(INT_FAST64_MAX >= 9223372036854775807LL, "INT_FAST64_MAX >= 9223372036854775807LL");
// UINT_FASTN_MAX // UINT_FASTN_MAX
▲ Show 20 Lines • Show All 90 Lines • Show Last 20 Lines

test/std/language.support/cstdint/cstdint.syn/cstdint.pass.cpp

Show First 20 Lines • Show All 166 Lines • ▼ Show 20 Linesint main()
static_assert(sizeof(std::uintmax_t) >= sizeof(unsigned long long), static_assert(sizeof(std::uintmax_t) >= sizeof(unsigned long long),
"sizeof(std::uintmax_t) >= sizeof(unsigned long long)"); "sizeof(std::uintmax_t) >= sizeof(unsigned long long)");
static_assert(std::is_unsigned<std::uintmax_t>::value, static_assert(std::is_unsigned<std::uintmax_t>::value,
"std::is_unsigned<std::uintmax_t>::value"); "std::is_unsigned<std::uintmax_t>::value");
// INTN_MIN // INTN_MIN
static_assert(INT8_MIN == -128, "INT8_MIN == -128"); static_assert(INT8_MIN == -128, "INT8_MIN == -128");
static_assert(INT16_MIN == -32768, "INT16_MIN == -32768"); static_assert(INT16_MIN == -32768, "INT16_MIN == -32768");
static_assert(INT32_MIN == -2147483648U, "INT32_MIN == -2147483648"); static_assert(INT32_MIN == -2147483647 - 1, "INT32_MIN == -2147483648");
static_assert(INT64_MIN == -9223372036854775808ULL, "INT64_MIN == -9223372036854775808LL"); static_assert(INT64_MIN == -9223372036854775807LL - 1, "INT64_MIN == -9223372036854775808LL");
// INTN_MAX // INTN_MAX
static_assert(INT8_MAX == 127, "INT8_MAX == 127"); static_assert(INT8_MAX == 127, "INT8_MAX == 127");
static_assert(INT16_MAX == 32767, "INT16_MAX == 32767"); static_assert(INT16_MAX == 32767, "INT16_MAX == 32767");
static_assert(INT32_MAX == 2147483647, "INT32_MAX == 2147483647"); static_assert(INT32_MAX == 2147483647, "INT32_MAX == 2147483647");
static_assert(INT64_MAX == 9223372036854775807LL, "INT64_MAX == 9223372036854775807LL"); static_assert(INT64_MAX == 9223372036854775807LL, "INT64_MAX == 9223372036854775807LL");
// UINTN_MAX // UINTN_MAX
static_assert(UINT8_MAX == 255, "UINT8_MAX == 255"); static_assert(UINT8_MAX == 255, "UINT8_MAX == 255");
static_assert(UINT16_MAX == 65535, "UINT16_MAX == 65535"); static_assert(UINT16_MAX == 65535, "UINT16_MAX == 65535");
static_assert(UINT32_MAX == 4294967295U, "UINT32_MAX == 4294967295"); static_assert(UINT32_MAX == 4294967295U, "UINT32_MAX == 4294967295");
static_assert(UINT64_MAX == 18446744073709551615ULL, "UINT64_MAX == 18446744073709551615ULL"); static_assert(UINT64_MAX == 18446744073709551615ULL, "UINT64_MAX == 18446744073709551615ULL");
// INT_FASTN_MIN // INT_FASTN_MIN
static_assert(INT_FAST8_MIN <= -128, "INT_FAST8_MIN <= -128"); static_assert(INT_FAST8_MIN <= -128, "INT_FAST8_MIN <= -128");
static_assert(INT_FAST16_MIN <= -32768, "INT_FAST16_MIN <= -32768"); static_assert(INT_FAST16_MIN <= -32768, "INT_FAST16_MIN <= -32768");
static_assert(INT_FAST32_MIN <= -2147483648U, "INT_FAST32_MIN <= -2147483648"); static_assert(INT_FAST32_MIN <= -2147483647 - 1, "INT_FAST32_MIN <= -2147483648");
static_assert(INT_FAST64_MIN <= -9223372036854775808ULL, "INT_FAST64_MIN <= -9223372036854775808LL"); static_assert(INT_FAST64_MIN <= -9223372036854775807LL - 1, "INT_FAST64_MIN <= -9223372036854775808LL");
// INT_FASTN_MAX // INT_FASTN_MAX
static_assert(INT_FAST8_MAX >= 127, "INT_FAST8_MAX >= 127"); static_assert(INT_FAST8_MAX >= 127, "INT_FAST8_MAX >= 127");
static_assert(INT_FAST16_MAX >= 32767, "INT_FAST16_MAX >= 32767"); static_assert(INT_FAST16_MAX >= 32767, "INT_FAST16_MAX >= 32767");
static_assert(INT_FAST32_MAX >= 2147483647, "INT_FAST32_MAX >= 2147483647"); static_assert(INT_FAST32_MAX >= 2147483647, "INT_FAST32_MAX >= 2147483647");
static_assert(INT_FAST64_MAX >= 9223372036854775807LL, "INT_FAST64_MAX >= 9223372036854775807LL"); static_assert(INT_FAST64_MAX >= 9223372036854775807LL, "INT_FAST64_MAX >= 9223372036854775807LL");
// UINT_FASTN_MAX // UINT_FASTN_MAX
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