# Data Options

This section contains descriptions for compiler options that pertain to the treatment of data. They are listed in alphabetical order.

Parent topic: Compiler Options

- align
  Tells the compiler how to align certain data items.
- auto
  Causes all local, non-SAVEd variables to be allocated to the run-time stack.
- auto-scalar, Qauto-scalar
  Causes scalar variables of intrinsic types INTEGER, REAL, COMPLEX, and LOGICAL that do not have the SAVE attribute to be allocated to the run-time stack.
- convert
  Specifies the format of unformatted files containing numeric data.
- double-size
  Specifies the default KIND for DOUBLE PRECISION and DOUBLE COMPLEX declarations, constants, functions, and intrinsics.
- dyncom, Qdyncom
  Enables dynamic allocation of common blocks at run time.
- falign-functions, Qfnalign
  Tells the compiler to align procedures on an optimal byte boundary.
- falign-loops, Qalign-loops
  Aligns loops to a power-of-two byte boundary. This feature is only available for ifort.
- falign-stack
  Tells the compiler the stack alignment to use on entry to routines. This is a deprecated option that may be removed in a future release. This feature is only available for ifort.
- fcommon
  Determines whether the compiler treats common symbols as global definitions. This feature is only available for ifort.
- fkeep-static-consts, Qkeep-static-consts
  Tells the compiler to preserve allocation of variables that are not referenced in the source. This feature is only available for ifort.
- fmath-errno
  Tells the compiler that errno can be reliably tested after calls to standard math library functions. This feature is only available for ifort.
- fminshared
  Specifies that a compilation unit is a component of a main program and should not be linked as part of a shareable object. This feature is only available for ifort.
- fpconstant
  Tells the compiler that single-precision constants assigned to double-precision variables should be evaluated in double precision.
- fpic
  Determines whether the compiler generates position-independent code.
- fpie
  Tells the compiler to generate position-independent code. The generated code can only be linked into executables.
- fstack-protector
  Enables or disables stack overflow security checks for certain (or all) routines.
- fstack-security-check
  Determines whether the compiler generates code that detects some buffer overruns.
- fvisibility
  Specifies the default visibility for global symbols or the visibility for symbols in a file. This feature is only available for ifort.
- fzero-initialized-in-bss, Qzero-initialized-in-bss
  Determines whether the compiler places in the DATA section any variables explicitly initialized with zeros. This feature is only available for ifort.
- Gs
  Lets you control the threshold at which the stack checking routine is called or not called. This feature is only available for ifort.
- GS
  Determines whether the compiler generates code that detects some buffer overruns.
- homeparams
  Tells the compiler to store parameters passed in registers to the stack. This feature is only available for ifort.
- init, Qinit
  Lets you initialize a class of variables to zero or to various numeric exceptional values.
- intconstant
  Tells the compiler to use FORTRAN 77 semantics to determine the kind parameter for integer constants.
- integer-size
  Specifies the default KIND for integer and logical variables.
- mcmodel
  Tells the compiler to use a specific memory model to generate code and store data.
- mdynamic-no-pic
  Generates code that is not position-independent but has position-independent external references. This feature is only available for ifort.
- no-bss-init, Qnobss-init
  Tells the compiler to place in the DATA section any uninitialized variables and explicitly zero-initialized variables. This is a deprecated option that may be removed in a future release. This feature is only available for ifort.
- Qsfalign
  Specifies stack alignment for functions. This is a deprecated option that may be removed in a future release. This feature is only available for ifort.
- real-size
  Specifies the default KIND for real and complex declarations, constants, functions, and intrinsics.
- save, Qsave
  Causes variables to be placed in static memory.
- zero, Qzero
  Initializes to zero variables of intrinsic type INTEGER, REAL, COMPLEX, or LOGICAL that are not yet initialized. This is a deprecated option. The replacement option is /Qinit:[no]zero or -init=[no]zero.