SPEC OMP2012 Flag Description for GNU Fortran/C/C++ Compilers 6.2 for 64 Bit Linux

Sections

Selecting one of the following will take you directly to that section:

Optimization Flags
Portability Flags
Compiler Flags
Other Flags

Optimization Flags

-O3
-fopenmp

- -O3
- gcc_l, gpp_l, gfortran_l, gcc_w, gpp_w
- -O3\b
- Chooses generally optimal flags for the target platform.
- -fopenmp
- gcc_l, gpp_l, gfortran_l, gcc_w, gpp_w
- -fopenmp\b
- Use the -fopenmp option to instruct the compiler to interpret user-inserted OpenMP shared-memory parallel programming directives and generate an executable file which will utilize multiple processors in a shared-memory parallel system.

Portability Flags

-ffree-form
-ffixed-form
-fno-range-check

- -ffree-form
- gfortran_l
- -ffree-form\b
- Process Fortran source using free form specifications. By default files with a .f90, .F90, .f95 or .F95 extension use freeform formatting.<\p>
- -ffixed-form
- gfortran_l
- -ffixed-form\b
- Process Fortran source using fixed form specifications.<\p>
- -fno-range-check
- gfortran_l
- -fno-range-check\b
- Disable range checking on results of simplification of constant expressions during compilation.<\p>

Compiler Flags

gcc.exe
g++.exe
gfortran.exe
gcc
g++
gfortran

- gcc.exe
- gcc\.exe\b
- The GNU C compiler for Windows.
- g++.exe
- g++\.exe\b
- The GNU C++ compiler for Windows.
- gfortran.exe
- gfortran\.exe\b
- The GNU Fortran 95 compiler for Windows.
- gcc
- gcc\b
- The GNU C compiler for Linux.
- g++
- g[+]+
- The GNU C++ compiler for Linux.
- gfortran
- gfortran\b
- The GNU Fortran 95 compiler for Linux.

Other Flags

-w

- -w
- gcc_l, gpp_l, gfortran_l, gcc_w, gpp_w
- -w\b
- Disable warning messages.

Shell, Environment, and Other Software Settings

OMP_DYNAMIC=FALSE: OMP_DYNAMIC=[ 1 | 0 ] Enables (1) or disables (0) the dynamic adjustment of the number of threads.
OMP_NESTED=FALSE: OMP_NESTED=[ 1 | 0 ] Enables (1) or disables (0) nested parallelism.