GNU C Library 2.40 Released With New C23 Features & New Performance Tunables

GNU C Library "glibc" 2.40 is now available with more C23 features being enabled as well as some new performance tunables on x86_64 and AArch64 along with other improvements to this widely used libc implementation.

Glibc 2.40 was tagged on Sunday and brings with it many new features. Some of the GNU C Library 2.40 highlights include:

- Glibc now supports a feature test macro _ISOC23_SOURCE to enable features from the ISO C23 standard.

- The ISO C23 function families are now supported in the math.h header file. The families include functions for float, double, long double, _FloatN and _FloatNx, and a type-generic macro in tgmath.h.

- The new tunable "glibc.rtld.enable_secure" can be used to run a program as if it were a setuid process.

- The fortify functionality has been improved for building programs with Clang against the GNU C Library.

- Many new functions for the vector library on AArch64: acosh, asinh, atanh, cbrt, cosh, erf, erfc, hypot, pow, sinh, tanh.

- Glibc on x86_64 can now use non-temporal stores to improve the performance of large writes when enabled via the new x86_memset_non_temporal_threshold tunable.

- Many bug fixes along with several security fixes.

- Glibc tuning for Qualcomm's Oryon CPU core.

For those building Glibc from source can grab the new GNU C Library 2.40 version from