.. Copyright 1988-2022 Free Software Foundation, Inc. This is part of the GCC manual. For copying conditions, see the copyright.rst file. .. index:: Environment Variable .. _omp_stacksize: OMP_STACKSIZE -- Set default thread stack size ********************************************** Description: Set the default thread stack size in kilobytes, unless the number is suffixed by ``B``, ``K``, ``M`` or ``G``, in which case the size is, respectively, in bytes, kilobytes, megabytes or gigabytes. This is different from ``pthread_attr_setstacksize`` which gets the number of bytes as an argument. If the stack size cannot be set due to system constraints, an error is reported and the initial stack size is left unchanged. If undefined, the stack size is system dependent. Reference: :openmp:`4.5`, Section 4.7