On Fri, Mar 06, 2026 at 04:06:49PM +0100, Robin Dapp wrote:
> Like this? Tested as before.
Yep, but see below.
> +#if __BITINT_MAXWIDTH__ >= 60692
> +__attribute__((__noipa__)) __attribute__((__cold__)) void
You can use __attribute__((__noipa__, __cold__)) or
[[gnu::noipa, gnu::cold]].
Which function used to be miscompiled? foo0 or its caller?
> +foo0 (int, int, int, int,
> + _BitInt (3) sb3_0, char, char, char,
> + char, char, char, char, char,
> + char,char,char,char,
> + _BitInt (5), _BitInt (5), short, short, char,
> + short, short, char, int,
> + int, int, int, int, char,
> + long, long, long, long, long,
> + long, char, char, char, __int128,
> + __int128, __int128, __int128, __int128,
> + __int128, char, _BitInt (129), _BitInt (129),
> + _BitInt (255), _BitInt (255), _BitInt (256), _BitInt (256),
> + _BitInt (257), _BitInt (257), _BitInt (511), _BitInt (511),
> + _BitInt (512), _BitInt (512), _BitInt (513), _BitInt (513),
> + _BitInt (1023), _BitInt (1023), _BitInt (1024),
> + _BitInt (1024), _BitInt (1025), _BitInt (1025), _BitInt (331),
> + _BitInt (331), _BitInt (412), _BitInt (412), _BitInt (985),
> + _BitInt (985), _BitInt (60692), _BitInt (60692), char, char,
> + char, char, short, short, char, char, short, short, unsigned,
> + int, v64s8, v64s8, v64s16, v64s16, v64s32, v64s32, long, long,
> + v128s8, v128s8, short, v128s16, int, v128s32, long, v128s64,
> + __int128, __int128, v256s8, v256s8, v256s16, v256s16, v256s32,
> + v256s32, v256s64, v256s64, v256s128, v256s128, v512s8, v512s8,
> + v512s16, v512s16, v512s32, v512s32, v512s64, v512s64,
> + v512s128, v512s128, char *ret)
> +{
> + *ret = sb3_0;
> +}
> +#endif
> +
> +void xprintf(const char *s, ...)
> +{
> + __builtin_va_list arg;
> + __builtin_va_start(arg, s);
> + int x = __builtin_va_arg(arg, int);
> + if (x != 0xfc)
> + __builtin_abort();
> + __builtin_va_end(arg);
> +}
> +
> +int
> +main ()
> +{
> +#if __BITINT_MAXWIDTH__ >= 60692
> + char x;
> + foo0 (0, 0, 0, 0, -4, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, -11, 9, 2, 95,
> + 67, -24064, 0, 5, 6, 7, 0, 8, 9, 20, 4, 3, 6018427387903, 53,
> + 505857273496, 255, 6, 0, 18446744073709551612uwb,
> + 70141183460469231731687303715884105726uwb,
> + 0x1ab7415df78c5d6355b5bf722d2c32wb, 18266202578652419339uwb,
> + 9594516560314871492uwb, 18446744073709551615uwb, 0,
> + 404678514476015038251338572701189uwb, 0,
> +
> 6044618658097711785492504343953926634992332820282019728792003956564819964uwb,
> + 0, 0,
> +
> 6044618658097711785492504343953926634992332820282019728792003956564819967uwb,
> + 0,
> + 0x10000000000000000000000000000000000000000000000000000000000000000wb,
> 0, 1, 0, 606316039853739674053402528525595147334676uwb, 0,
> +
> 407807929942597099574024998205846127479363981533648751059337645126787177315524892796678197877342278766808798337256961671307362116160553321514205699439425uwb,
> + 0,
> +
> 40449424473557664318357520289433168951375240783177119330601884005280028469967848339414697442203604155532867238014401323013014363877264556147687333148794044698496604162935270824544179699376777403364901791967663653826658703420189949487003960239619175525152082242122474284732uwb,
> +
> 90772930519078902473361797697894230657273430081157732675805500963132708477322407536021120113879871393357658789768814416622492847430639474124377767893424865485276302219601246094119453082952085005768838150682342462881473913110540827237163350510684586298239947245938479716304835356329623282435531uwb,
> + 0, 0,
> +
> 30203714894603546035770925859109268843954143792619895153655326951406405759993601526034894524347802740350892957243539456uwb,
> + 0,
> +
> 0x24c07bd236a355dac41c3e00fed83a2c01d47d7e7c155128f8474ab8acd075fe3be2661e9ba3b0498c2wb,
> + 0,
> +
> -0x273d7a44735564a706be6f876e8c09a64c065028fc8719feace6b4ad22b722fc6628809c1bcfda902d563717b88876aa068496bwb,
> + 0, 5, 0, 4, 0, 5, 0, 0115, 3, 92, 0, 1, 840, 839, 35, 4095, (v64s8)
> + { }, (v64s8)
> + { 3, -0x4 }, (v64s16)
> + { }, (v64s16)
> + { }, (v64s32)
> + { }, (v64s32)
> + { }, 7, 40, (v128s8)
> + { }, (v128s8)
> + { }, 126, (v128s16)
> + { }, 95, (v128s32)
> + { }, 6, (v128s64)
> + { }, 18446462603027742720uwb, 11842991817553718011uwb, (v256s8)
> + { 227, 84, 73, 5, 2, 45, 107, 55, 16, 128, 23, 17, 1, 226, 15 },
> + (v256s8)
> + { 9, 111, 108, 19, 98, 27, 97, -0xe }, (v256s16)
> + { 1, 167, 65280, 35, 15286, 9, 182, 13126, 15 }, (v256s16)
> + { 72, 381, 185, 619, 978, 926, 42 }, (v256s32)
> + { 20, 72, 905, 207, 63, 40 }, (v256s32)
> + { 5, 503, 1, 152, 5519391 }, (v256s64)
> + { 1280 }, (v256s64)
> + { 94, 8851183291103289765uwb, 526 }, (v256s128)
> + { 15013856701581711399uwb }, (v256s128)
> + { 10389555769421265252uwb, 15766594437788011035uwb }, (v512s8)
> + { 104, 131, 5, 21, 32, 127, 75, 54, 232, 1, 82, 255, 28, 178, 1,
> + 121, 1, 14, 210, 240, 140, 53, 4, 91, 204, 78, 130, 76, 212, 52, 1,
> + 200, 11, 25, 251, 41, 88, 12, 3, 59 }, (v512s8)
> + { 13, 10, 48, -0x2f, 67, 85, 87, 123, 8, 26, 83, 114, 51, 6, 96,
> + -0x1c, 115, 49, 86, 103, 93, 31, -0x6, 112, 1, 7, -0xc, 18, 47, 5,
> + -0xf, 3 }, (v512s16)
> + { 4094, 64492, 855, 61680, 27, 47569, 55, 65534, 76, -1024, 30,
> + 254, 280, 11, 10, 14, 2, 4095, 3, 111, 65535, 67, 24289, 32, 25604,
> + 26, 65535, 98, 65533, 5 }, (v512s16)
> + { 615, 2032, 54, 52, 015, 45, 24, 6, 7, 68, 24015, 380, 3315, 5, 8,
> + 23, -0xf, 62, 82, 4 }, (v512s32)
> + { 54, 4294967294, 6, 16, 9, 13, 300, 80000000, 700, 600, 93, 040,
> + 15 }, (v512s32)
> + { 515, 3, 14, 10, 2, 80, 39, 215, 7, 3, 4 }, (v512s64)
> + { 4, 9, 5, 3, 505 }, (v512s64)
> + { 904293909041052234uwb, 4 }, (v512s128)
> + { 9223372036854775808uwb, 1, 4073709551612 }, (v512s128)
> + { 7, 30391054, 18446742974197923807uwb }, &x);
> + for (unsigned i = 0; i < sizeof(x); i++) xprintf("%02x", (int)(unsigned
> char)x);
If the callee, can't this just do
if ((unsigned char)x != 0xfc)
__builtin_abort ();
instead?
If the caller (i.e. main), why isn't xprintf also noipa? And why it is done
in a loop with a single iteration? Can't xprintf be modified to take const
char * and int arguments and avoid stdarg?
Jakub
