diff options
Diffstat (limited to 'toolchain/musl/patches/054-fix-strtod-and-strtof-rounding-with-many-trailing-zeros.patch')
| -rw-r--r-- | toolchain/musl/patches/054-fix-strtod-and-strtof-rounding-with-many-trailing-zeros.patch | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/toolchain/musl/patches/054-fix-strtod-and-strtof-rounding-with-many-trailing-zeros.patch b/toolchain/musl/patches/054-fix-strtod-and-strtof-rounding-with-many-trailing-zeros.patch new file mode 100644 index 0000000000..3d9211c022 --- /dev/null +++ b/toolchain/musl/patches/054-fix-strtod-and-strtof-rounding-with-many-trailing-zeros.patch @@ -0,0 +1,36 @@ +From d184a09e0529f33d8ddddb8825039133483a2c41 Mon Sep 17 00:00:00 2001 +From: Szabolcs Nagy <nsz@port70.net> +Date: Sun, 4 Sep 2016 04:46:00 +0200 +Subject: fix strtod and strtof rounding with many trailing zeros + +in certain cases excessive trailing zeros could cause incorrect +rounding from long double to double or float in decfloat. + +e.g. in strtof("9444733528689243848704.000000", 0) the argument +is 0x1.000001p+73, exactly halfway between two representible floats, +this incorrectly got rounded to 0x1.000002p+73 instead of 0x1p+73, +but with less trailing 0 the rounding was fine. + +the fix makes sure that the z index always points one past the last +non-zero digit in the base 10^9 representation, this way trailing +zeros don't affect the rounding logic. +--- + src/internal/floatscan.c | 3 +++ + 1 file changed, 3 insertions(+) + +diff --git a/src/internal/floatscan.c b/src/internal/floatscan.c +index eef70df..80305ee 100644 +--- a/src/internal/floatscan.c ++++ b/src/internal/floatscan.c +@@ -172,6 +172,9 @@ static long double decfloat(FILE *f, int c, int bits, int emin, int sign, int po + return sign * (long double)x[0] * p10s[rp-10]; + } + ++ /* Drop trailing zeros */ ++ for (; !x[z-1]; z--); ++ + /* Align radix point to B1B digit boundary */ + if (rp % 9) { + int rpm9 = rp>=0 ? rp%9 : rp%9+9; +-- +cgit v0.11.2 |