diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/backend/access/hash/hashfunc.c | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/src/backend/access/hash/hashfunc.c b/src/backend/access/hash/hashfunc.c index a127f3f8b1b..8d4c450b934 100644 --- a/src/backend/access/hash/hashfunc.c +++ b/src/backend/access/hash/hashfunc.c @@ -26,6 +26,11 @@ #include "postgres.h" +#ifdef _MSC_VER +#include <float.h> /* for _isnan */ +#endif +#include <math.h> + #include "access/hash.h" #include "utils/builtins.h" @@ -105,6 +110,14 @@ hashfloat4(PG_FUNCTION_ARGS) PG_RETURN_UINT32(0); /* + * Similarly, NaNs can have different bit patterns but they should all + * compare as equal. For backwards-compatibility reasons we force them to + * have the hash value of a standard NaN. + */ + if (isnan(key)) + key = get_float4_nan(); + + /* * To support cross-type hashing of float8 and float4, we want to return * the same hash value hashfloat8 would produce for an equal float8 value. * So, widen the value to float8 and hash that. (We must do this rather @@ -129,6 +142,14 @@ hashfloat8(PG_FUNCTION_ARGS) if (key == (float8) 0) PG_RETURN_UINT32(0); + /* + * Similarly, NaNs can have different bit patterns but they should all + * compare as equal. For backwards-compatibility reasons we force them to + * have the hash value of a standard NaN. + */ + if (isnan(key)) + key = get_float8_nan(); + return hash_any((unsigned char *) &key, sizeof(key)); } |