Which ifort

I find no -O4 in my makefiles. Any suggestions? Last edited by janbor on Mon Jul 30, am, edited 1 time in total. Which ifort actually works 4 Post by janbor » Tue Jul 31, am I solved the problem by changing the -O3 option, in Intels ifort makefile, to -O1 Jan. Last edited by janbor on Tue Jul 31, am, edited 1 time in total. I would like to know which ifc and atlas library are you using. I am trying to compile vasp with ifc Intel Fortran ifort. Instructions for users:.

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Now live: A fully responsive profile. Related 1. Hot Network Questions. Question feed. Stack Overflow works best with JavaScript enabled. Accept all cookies Customize settings. In v we will test if this is resolved by the recent code updates. Path to the netCDF library folder e. Path to the netCDF Fortran library folder e. Turns off all optimizations. Math expressions will be evaluated in the same order in which they are written, which is necessary for debugging.

If you are using a debugger such as Totalview , compile with -g -O0. Enables optimizations for speed and disables some optimizations that increase code size and affect speed. The -O1 option may improve performance for applications with very large code size, many branches, and execution time not dominated by code within loops.

Setting -O1 automatically sets the following options: -funroll-loops0 , -nofltconsistency same as -mno-ieee-fp , -fomit-frame-pointer , -ftz. Enables optimizations for speed. This is the generally recommended optimization level. Enables -O2 optimizations plus more aggressive optimizations, such as prefetching, scalar replacement, and loop and memory access transformations. Enables optimizations for maximum speed, such as: Loop unrolling, including instruction scheduling Code replication to eliminate branches Padding the size of certain power-of-two arrays to allow more efficient cache use.

Turns on the C-preprocessor, to evaluate if and define statements in the source code. Suppresses all compiler warnings. This is mainly a convenience to prevent excessive output to the screen or log file. Optimizes the source code for speed, without taking too many liberties with numerical precision. For more information, please see the optimization options section above.

This option places local variables scalars and arrays of all types , except those declared as SAVE , on the run-time stack. Prevents the compiler from padding bytes anywhere in common blocks and structures. Padding can affect numerical precision. Specifies that the format will be big endian for integer data and big endian IEEE floating-point for real and complex data. Rounds intermediate results to source-defined precision and enables value-safe optimizations.

Basically, this tells the compiler not to take too many liberties with how numerical expressions are evaluated.

For more information about this option, please see our precision-safe optimization section below. This option tells the compiler to generate extra information in the object file to provide source file traceback information when a severe error occurs at run time. When the severe error occurs, source file, routine name, and line number correlation information is displayed along with call stack hexadecimal addresses program counter trace.

This option increases the size of the executable program, but has no impact on run-time execution speeds. It functions independently of the debug option. This avoids a specific type of memory error that can occur if you compile GEOS-Chem for use with an extremely high-resolution grid e.

It causes Intel-provided libraries to be linked in dynamically instead of statically which is the default. This option enables interprocedural optimization between files.