70d2687d85c314963cf280759b23fd4573ff0d82
if the requested precision is close to INT_MAX, adding LDBL_MANT_DIG/3+8 overflows. in practice the resulting undefined behavior manifests as a large negative result, which is then used to compute the new end pointer (z) with a wildly out-of-bounds value (more overflow, more undefined behavior). the end result is at least incorrect output and character count (return value); worse things do not seem to happen, but detailed analysis has not been done. this patch fixes the overflow by performing the intermediate computation as unsigned; after division by 9, the final result necessarily fits in int.
musl libc
musl, pronounced like the word "mussel", is an MIT-licensed
implementation of the standard C library targetting the Linux syscall
API, suitable for use in a wide range of deployment environments. musl
offers efficient static and dynamic linking support, lightweight code
and low runtime overhead, strong fail-safe guarantees under correct
usage, and correctness in the sense of standards conformance and
safety. musl is built on the principle that these goals are best
achieved through simple code that is easy to understand and maintain.
The 1.1 release series for musl features coverage for all interfaces
defined in ISO C99 and POSIX 2008 base, along with a number of
non-standardized interfaces for compatibility with Linux, BSD, and
glibc functionality.
For basic installation instructions, see the included INSTALL file.
Information on full musl-targeted compiler toolchains, system
bootstrapping, and Linux distributions built on musl can be found on
the project website:
http://www.musl-libc.org/