llvm-project/clang/test/Sema/tautological-constant-compa...

673 lines
16 KiB
C

// RUN: %clang_cc1 -triple x86_64-linux-gnu -fsyntax-only -Wtautological-constant-in-range-compare -DTEST=2 -verify %s
// RUN: %clang_cc1 -triple x86_64-linux-gnu -fsyntax-only -Wtautological-constant-in-range-compare -DTEST=2 -verify -x c++ %s
// RUN: %clang_cc1 -triple x86_64-linux-gnu -fsyntax-only -Wtautological-type-limit-compare -DTEST -verify %s
// RUN: %clang_cc1 -triple x86_64-linux-gnu -fsyntax-only -Wtautological-type-limit-compare -DTEST -verify -x c++ %s
// RUN: %clang_cc1 -triple x86_64-linux-gnu -fsyntax-only -Wtype-limits -DTEST -verify %s
// RUN: %clang_cc1 -triple x86_64-linux-gnu -fsyntax-only -Wtype-limits -DTEST -verify -x c++ %s
// RUN: %clang_cc1 -triple x86_64-linux-gnu -fsyntax-only -Wextra -Wno-sign-compare -verify=silent %s
// RUN: %clang_cc1 -triple x86_64-linux-gnu -fsyntax-only -Wextra -Wno-sign-compare -verify=silent -x c++ %s
// RUN: %clang_cc1 -triple x86_64-linux-gnu -fsyntax-only -Wall -verify=silent %s
// RUN: %clang_cc1 -triple x86_64-linux-gnu -fsyntax-only -Wall -verify=silent -x c++ %s
// RUN: %clang_cc1 -triple x86_64-linux-gnu -fsyntax-only -verify=silent %s
// RUN: %clang_cc1 -triple x86_64-linux-gnu -fsyntax-only -verify=silent -x c++ %s
#ifndef TEST
// silent-no-diagnostics
#endif
int value(void);
#define macro(val) val
#ifdef __cplusplus
template<typename T>
void TFunc() {
// Make sure that we do warn for normal variables in template functions !
unsigned char c = value();
#ifdef TEST
if (c > 255) // expected-warning {{comparison 'unsigned char' > 255 is always false}}
return;
#else
if (c > 255)
return;
#endif
if (c > macro(255))
return;
T v = value();
if (v > 255)
return;
if (v > 32767)
return;
}
#endif
int main(void)
{
#ifdef __cplusplus
TFunc<unsigned char>();
TFunc<signed short>();
#endif
short s = value();
#ifdef TEST
if (s == 32767)
return 0;
if (s != 32767)
return 0;
if (s < 32767)
return 0;
if (s <= 32767) // expected-warning {{comparison 'short' <= 32767 is always true}}
return 0;
if (s > 32767) // expected-warning {{comparison 'short' > 32767 is always false}}
return 0;
if (s >= 32767)
return 0;
if (32767 == s)
return 0;
if (32767 != s)
return 0;
if (32767 < s) // expected-warning {{comparison 32767 < 'short' is always false}}
return 0;
if (32767 <= s)
return 0;
if (32767 > s)
return 0;
if (32767 >= s) // expected-warning {{comparison 32767 >= 'short' is always true}}
return 0;
// FIXME: assumes two's complement
if (s == -32768)
return 0;
if (s != -32768)
return 0;
if (s < -32768) // expected-warning {{comparison 'short' < -32768 is always false}}
return 0;
if (s <= -32768)
return 0;
if (s > -32768)
return 0;
if (s >= -32768) // expected-warning {{comparison 'short' >= -32768 is always true}}
return 0;
if (-32768 == s)
return 0;
if (-32768 != s)
return 0;
if (-32768 < s)
return 0;
if (-32768 <= s) // expected-warning {{comparison -32768 <= 'short' is always true}}
return 0;
if (-32768 > s) // expected-warning {{comparison -32768 > 'short' is always false}}
return 0;
if (-32768 >= s)
return 0;
// Note: both sides are promoted to unsigned long prior to the comparison, so
// it is perfectly possible for a short to compare greater than 32767UL.
if (s == 32767UL)
return 0;
if (s != 32767UL)
return 0;
if (s < 32767UL)
return 0;
if (s <= 32767UL)
return 0;
if (s > 32767UL)
return 0;
if (s >= 32767UL)
return 0;
if (32767UL == s)
return 0;
if (32767UL != s)
return 0;
if (32767UL < s)
return 0;
if (32767UL <= s)
return 0;
if (32767UL > s)
return 0;
if (32767UL >= s)
return 0;
enum { ULONG_MAX = (2UL * (unsigned long)__LONG_MAX__ + 1UL) };
if (s == 2UL * (unsigned long)__LONG_MAX__ + 1UL)
return 0;
if (s != 2UL * (unsigned long)__LONG_MAX__ + 1UL)
return 0;
if (s < 2UL * (unsigned long)__LONG_MAX__ + 1UL)
return 0;
if (s <= 2UL * (unsigned long)__LONG_MAX__ + 1UL) // expected-warning-re {{comparison 'short' <= {{.*}} is always true}}
return 0;
if (s > 2UL * (unsigned long)__LONG_MAX__ + 1UL) // expected-warning-re {{comparison 'short' > {{.*}} is always false}}
return 0;
if (s >= 2UL * (unsigned long)__LONG_MAX__ + 1UL)
return 0;
if (2UL * (unsigned long)__LONG_MAX__ + 1UL == s)
return 0;
if (2UL * (unsigned long)__LONG_MAX__ + 1UL != s)
return 0;
if (2UL * (unsigned long)__LONG_MAX__ + 1UL < s) // expected-warning-re {{comparison {{.*}} < 'short' is always false}}
return 0;
if (2UL * (unsigned long)__LONG_MAX__ + 1UL <= s)
return 0;
if (2UL * (unsigned long)__LONG_MAX__ + 1UL > s)
return 0;
if (2UL * (unsigned long)__LONG_MAX__ + 1UL >= s) // expected-warning-re {{comparison {{.*}} >= 'short' is always true}}
return 0;
// FIXME: assumes two's complement
if (s == -32768L)
return 0;
if (s != -32768L)
return 0;
if (s < -32768L) // expected-warning {{comparison 'short' < -32768 is always false}}
return 0;
if (s <= -32768L)
return 0;
if (s > -32768L)
return 0;
if (s >= -32768L) // expected-warning {{comparison 'short' >= -32768 is always true}}
return 0;
if (-32768L == s)
return 0;
if (-32768L != s)
return 0;
if (-32768L < s)
return 0;
if (-32768L <= s) // expected-warning {{comparison -32768 <= 'short' is always true}}
return 0;
if (-32768L > s) // expected-warning {{comparison -32768 > 'short' is always false}}
return 0;
if (-32768L >= s)
return 0;
#else
if (s == 32767)
return 0;
if (s != 32767)
return 0;
if (s < 32767)
return 0;
if (s <= 32767)
return 0;
if (s > 32767)
return 0;
if (s >= 32767)
return 0;
if (32767 == s)
return 0;
if (32767 != s)
return 0;
if (32767 < s)
return 0;
if (32767 <= s)
return 0;
if (32767 > s)
return 0;
if (32767 >= s)
return 0;
// FIXME: assumes two's complement
if (s == -32768)
return 0;
if (s != -32768)
return 0;
if (s < -32768)
return 0;
if (s <= -32768)
return 0;
if (s > -32768)
return 0;
if (s >= -32768)
return 0;
if (-32768 == s)
return 0;
if (-32768 != s)
return 0;
if (-32768 < s)
return 0;
if (-32768 <= s)
return 0;
if (-32768 > s)
return 0;
if (-32768 >= s)
return 0;
if (s == 32767UL)
return 0;
if (s != 32767UL)
return 0;
if (s < 32767UL)
return 0;
if (s <= 32767UL)
return 0;
if (s > 32767UL)
return 0;
if (s >= 32767UL)
return 0;
if (32767UL == s)
return 0;
if (32767UL != s)
return 0;
if (32767UL < s)
return 0;
if (32767UL <= s)
return 0;
if (32767UL > s)
return 0;
if (32767UL >= s)
return 0;
// FIXME: assumes two's complement
if (s == -32768L)
return 0;
if (s != -32768L)
return 0;
if (s < -32768L)
return 0;
if (s <= -32768L)
return 0;
if (s > -32768L)
return 0;
if (s >= -32768L)
return 0;
if (-32768L == s)
return 0;
if (-32768L != s)
return 0;
if (-32768L < s)
return 0;
if (-32768L <= s)
return 0;
if (-32768L > s)
return 0;
if (-32768L >= s)
return 0;
#endif
if (s == 0)
return 0;
if (s != 0)
return 0;
if (s < 0)
return 0;
if (s <= 0)
return 0;
if (s > 0)
return 0;
if (s >= 0)
return 0;
if (0 == s)
return 0;
if (0 != s)
return 0;
if (0 < s)
return 0;
if (0 <= s)
return 0;
if (0 > s)
return 0;
if (0 >= s)
return 0;
unsigned short us = value();
#ifdef TEST
if (us == 65535)
return 0;
if (us != 65535)
return 0;
if (us < 65535)
return 0;
if (us <= 65535) // expected-warning {{comparison 'unsigned short' <= 65535 is always true}}
return 0;
if (us > 65535) // expected-warning {{comparison 'unsigned short' > 65535 is always false}}
return 0;
if (us >= 65535)
return 0;
if (65535 == us)
return 0;
if (65535 != us)
return 0;
if (65535 < us) // expected-warning {{comparison 65535 < 'unsigned short' is always false}}
return 0;
if (65535 <= us)
return 0;
if (65535 > us)
return 0;
if (65535 >= us) // expected-warning {{comparison 65535 >= 'unsigned short' is always true}}
return 0;
if (us == 65535UL)
return 0;
if (us != 65535UL)
return 0;
if (us < 65535UL)
return 0;
if (us <= 65535UL) // expected-warning {{comparison 'unsigned short' <= 65535 is always true}}
return 0;
if (us > 65535UL) // expected-warning {{comparison 'unsigned short' > 65535 is always false}}
return 0;
if (us >= 65535UL)
return 0;
if (65535UL == us)
return 0;
if (65535UL != us)
return 0;
if (65535UL < us) // expected-warning {{comparison 65535 < 'unsigned short' is always false}}
return 0;
if (65535UL <= us)
return 0;
if (65535UL > us)
return 0;
if (65535UL >= us) // expected-warning {{comparison 65535 >= 'unsigned short' is always true}}
return 0;
#else
if (us == 65535)
return 0;
if (us != 65535)
return 0;
if (us < 65535)
return 0;
if (us <= 65535)
return 0;
if (us > 65535)
return 0;
if (us >= 65535)
return 0;
if (65535 == us)
return 0;
if (65535 != us)
return 0;
if (65535 < us)
return 0;
if (65535 <= us)
return 0;
if (65535 > us)
return 0;
if (65535 >= us)
return 0;
if (us == 65535UL)
return 0;
if (us != 65535UL)
return 0;
if (us < 65535UL)
return 0;
if (us <= 65535UL)
return 0;
if (us > 65535UL)
return 0;
if (us >= 65535UL)
return 0;
if (65535UL == us)
return 0;
if (65535UL != us)
return 0;
if (65535UL < us)
return 0;
if (65535UL <= us)
return 0;
if (65535UL > us)
return 0;
if (65535UL >= us)
return 0;
#endif
if (us == 32767)
return 0;
if (us != 32767)
return 0;
if (us < 32767)
return 0;
if (us <= 32767)
return 0;
if (us > 32767)
return 0;
if (us >= 32767)
return 0;
if (32767 == us)
return 0;
if (32767 != us)
return 0;
if (32767 < us)
return 0;
if (32767 <= us)
return 0;
if (32767 > us)
return 0;
if (32767 >= us)
return 0;
if (us == 32767UL)
return 0;
if (us != 32767UL)
return 0;
if (us < 32767UL)
return 0;
if (us <= 32767UL)
return 0;
if (us > 32767UL)
return 0;
if (us >= 32767UL)
return 0;
if (32767UL == us)
return 0;
if (32767UL != us)
return 0;
if (32767UL < us)
return 0;
if (32767UL <= us)
return 0;
if (32767UL > us)
return 0;
if (32767UL >= us)
return 0;
#if __SIZEOF_INT128__
__int128 i128 = value();
if (i128 == -1) // used to crash
return 0;
#endif
enum E {
yes,
no,
maybe
};
enum E e = (enum E)value();
if (e == yes)
return 0;
if (e != yes)
return 0;
if (e < yes)
return 0;
if (e <= yes)
return 0;
if (e > yes)
return 0;
if (e >= yes)
return 0;
if (yes == e)
return 0;
if (yes != e)
return 0;
if (yes < e)
return 0;
if (yes <= e)
return 0;
if (yes > e)
return 0;
if (yes >= e)
return 0;
if (e == maybe)
return 0;
if (e != maybe)
return 0;
if (e < maybe)
return 0;
if (e <= maybe)
return 0;
if (e > maybe)
return 0;
if (e >= maybe)
return 0;
if (maybe == e)
return 0;
if (maybe != e)
return 0;
if (maybe < e)
return 0;
if (maybe <= e)
return 0;
if (maybe > e)
return 0;
if (maybe >= e)
return 0;
// We only warn on out-of-range bitfields and expressions with limited range
// under -Wtantological-in-range-compare, not under -Wtype-limits, because
// the warning is not based on the type alone.
struct A {
int a : 3;
unsigned b : 3;
long c : 3;
unsigned long d : 3;
} a;
if (a.a < 3) {}
if (a.a < 4) {} // #bitfield1
if (a.b < 7) {}
if (a.b < 8) {} // #bitfield2
if (a.c < 3) {}
if (a.c < 4) {} // #bitfield3
if (a.d < 7) {}
if (a.d < 8) {} // #bitfield4
#if TEST == 2
// expected-warning@#bitfield1 {{comparison of 3-bit signed value < 4 is always true}}
// expected-warning@#bitfield2 {{comparison of 3-bit unsigned value < 8 is always true}}
// expected-warning@#bitfield3 {{comparison of 3-bit signed value < 4 is always true}}
// expected-warning@#bitfield4 {{comparison of 3-bit unsigned value < 8 is always true}}
#endif
if ((s & 0xff) < 0) {} // #valuerange1
if ((s & 0xff) < 1) {}
if ((s & -3) < -4) {}
if ((s & -3) < -3) {}
if ((s & -3) < 4u) {}
if ((s & -3) > 4u) {}
if ((s & -3) == 4u) {}
if ((s & -3) == 3u) {} // FIXME: Impossible.
if ((s & -3) == -5u) {}
if ((s & -3) == -4u) {}
#if TEST == 2
// expected-warning@#valuerange1 {{comparison of 8-bit unsigned value < 0 is always false}}
#endif
// FIXME: Our bit-level width tracking comes unstuck here: the second of the
// conditions below is also tautological, but we can't tell that because we
// don't track the actual range, only the bit-width.
if ((s ? 1 : 0) + (us ? 1 : 0) > 1) {}
if ((s ? 1 : 0) + (us ? 1 : 0) > 2) {}
if ((s ? 1 : 0) + (us ? 1 : 0) > 3) {} // #addrange1
#if TEST == 2
// expected-warning@#addrange1 {{comparison of 2-bit unsigned value > 3 is always false}}
#endif
// FIXME: The second and third comparisons are also tautological; 0x40000000
// is the greatest value that multiplying two int16s can produce.
if (s * s > 0x3fffffff) {}
if (s * s > 0x40000000) {}
if (s * s > 0x7ffffffe) {}
if (s * s > 0x7fffffff) {} // expected-warning {{result of comparison 'int' > 2147483647 is always false}}
if ((s & 0x3ff) * (s & 0x1f) > 0x7be0) {}
if ((s & 0x3ff) * (s & 0x1f) > 0x7be1) {} // FIXME
if ((s & 0x3ff) * (s & 0x1f) > 0x7ffe) {} // FIXME
if ((s & 0x3ff) * (s & 0x1f) > 0x7fff) {} // #mulrange1
#if TEST == 2
// expected-warning@#mulrange1 {{comparison of 15-bit unsigned value > 32767 is always false}}
#endif
if (a.a * a.b > 21) {} // FIXME
if (a.a * a.b > 31) {} // #mulrange2
#if TEST == 2
// expected-warning@#mulrange2 {{comparison of 6-bit signed value > 31 is always false}}
#endif
if (a.a - (s & 1) < -4) {}
if (a.a - (s & 1) < -7) {} // FIXME
if (a.a - (s & 1) < -8) {} // #subrange1
if (a.a - (s & 1) > 3) {} // FIXME: Can be < -4 but not > 3.
if (a.a - (s & 1) > 7) {} // #subrange2
if (a.a - (s & 7) < -8) {}
if (a.a - (s & 7) > 7) {} // FIXME: Can be < -8 but not > 7.
if (a.a - (s & 7) < -15) {}
if (a.a - (s & 7) < -16) {} // #subrange3
if (a.a - (s & 7) > 15) {} // #subrange4
if (a.b - (s & 1) > 6) {}
if (a.b - (s & 1) > 7) {} // #subrange5
if (a.b - (s & 7) < -8) {} // #subrange6
if (a.b - (s & 15) < -8) {}
if (a.b - (s & 15) < -16) {} // #subrange7
#if TEST == 2
// expected-warning@#subrange1 {{comparison of 4-bit signed value < -8 is always false}}
// expected-warning@#subrange2 {{comparison of 4-bit signed value > 7 is always false}}
// expected-warning@#subrange3 {{comparison of 5-bit signed value < -16 is always false}}
// expected-warning@#subrange4 {{comparison of 5-bit signed value > 15 is always false}}
// expected-warning@#subrange5 {{comparison of 4-bit signed value > 7 is always false}}
// expected-warning@#subrange6 {{comparison of 4-bit signed value < -8 is always false}}
// expected-warning@#subrange7 {{comparison of 5-bit signed value < -16 is always false}}
#endif
// a.a % 3 is in range [-2, 2], which we expand to [-4, 4)
if (a.a % 3 > 2) {}
if (a.a % 3 > 3) {} // #remrange1
if (a.a % 3 == -1) {}
if (a.a % 3 == -2) {}
if (a.a % 3 < -3) {} // FIXME
if (a.a % 3 < -4) {} // #remrange2
// a.b % 3 is in range [0, 3), which we expand to [0, 4)
if (a.b % 3 > 2) {}
if (a.b % 3 > 3) {} // #remrange3
if (a.b % 3 < 0) {} // #remrange4
#if TEST == 2
// expected-warning@#remrange1 {{comparison of 3-bit signed value > 3 is always false}}
// expected-warning@#remrange2 {{comparison of 3-bit signed value < -4 is always false}}
// expected-warning@#remrange3 {{comparison of 2-bit unsigned value > 3 is always false}}
// expected-warning@#remrange4 {{comparison of 2-bit unsigned value < 0 is always false}}
#endif
// Don't warn on non-constant-expression values that end up being a constant
// 0; we generally only want to warn when one side of the comparison is
// effectively non-constant.
if ("x"[1] == 0) {}
if (((void)s, 0) == 0) {}
return 1;
}