Packages with the alloca use flag

dev-libs / tre : Lightweight, robust, and efficient POSIX compliant regexp matching library

  • Enable if you want TRE to use alloca() instead of malloc() when allocating memory needed for regexec operations

sci-libs / kissfft : A Fast Fourier Transform (FFT) library that tries to Keep it Simple, Stupid

  • Use alloca(3) instead of malloc(3) for memory management