diff options
| -rw-r--r-- | src/internal/floatscan.c | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/src/internal/floatscan.c b/src/internal/floatscan.c index dbe07987..aa962f41 100644 --- a/src/internal/floatscan.c +++ b/src/internal/floatscan.c @@ -24,6 +24,8 @@ #define MASK (KMAX-1) +#define CONCAT2(x,y) x ## y +#define CONCAT(x,y) CONCAT2(x,y) static long long scanexp(FILE *f, int pok) { @@ -63,6 +65,8 @@ static long double decfloat(FILE *f, int c, int bits, int emin, int sign, int po int gotdig = 0, gotrad = 0; int rp; int e2; + int emax = -emin-bits+3; + int denormal = 0; long double y; long double frac=0; long double bias=0; @@ -250,6 +254,7 @@ static long double decfloat(FILE *f, int c, int bits, int emin, int sign, int po if (bits > LDBL_MANT_DIG+e2-emin) { bits = LDBL_MANT_DIG+e2-emin; if (bits<0) bits=0; + denormal = 1; } /* Calculate bias term to force rounding, move out lower bits */ @@ -280,11 +285,18 @@ static long double decfloat(FILE *f, int c, int bits, int emin, int sign, int po y += frac; y -= bias; - y = scalbnl(y, e2); - - if (!y) errno = ERANGE; + if ((e2+LDBL_MANT_DIG & INT_MAX) > emax-5) { + if (fabs(y) >= CONCAT(0x1p, LDBL_MANT_DIG)) { + if (denormal && bits==LDBL_MANT_DIG+e2-emin) + denormal = 0; + y *= 0.5; + e2++; + } + if (e2+LDBL_MANT_DIG>emax || (denormal && frac)) + errno = ERANGE; + } - return y; + return scalbnl(y, e2); } static long double hexfloat(FILE *f, int bits, int emin, int sign, int pok) |