HP UX Fortran Software manual 157

profiler	Programming tools that determine where a program spends its execution
	time. Profilers that come with HP Fortran 90 include prof, gprof, and
	CXperf.
R-S
roundoff error	The loss of precision that can occur as a result of floating-point arithmetic.
	Different orders of evaluating a floating-point expression can produce
	different accumulations of roundoff errors, which in turn can sometimes
	cause the expression to yield significantly different results.
row-major order	The method of storing C-language arrays in memory. (Fortran arrays are
	stored in column-major order.) Row-major order requires the rows of a
	two-dimensional array to be in contiguous memory locations. For example,
	given the array a[3][4], element a[0][0]would be stored in the first
	location, a[0][1]in the second, a[0][2]in the third, and so on.
segmentation	A type of exception that occurs when an executing program attempts to
violation	access memory outside of its allocated memory segment; also called a
	memory fault
serial execution	Program execution on only one processor at a time. See alsoparallel
	execution..
shared executable	An executable program whose text segment (that is, its code) can be shared
	by multiple processes.
shared library	A library of routines that can be linked to an executable program at runtime
	and shared by several programs simultaneously. The names of shared
	libraries have the .sl extension. See also archive library..
side effects	A condition that prevents the optimizer from parallelizing a loop. A
	procedure that is called within a loop has side effects if it communicates
	with the outside world other than through a return value.
signal	See trap.
stack overflow	An error condition that occurs when the runtime system attempts to allocate
	more memory from the stack than is available. This condition can occur
	when attempting to allocate very large arrays or when a recursive program
	is out of control.

static variable Variables that are allocated from static storage (sometimes referred to as the heap). Static variables have two characteristics of note:

•They preserve their value for the lifetime of the program.

•They are initialized when they are allocated.

By default, program variables in HP Fortran 90 are automatic

stream I/O	A type of I/O that is based on the concept of a stream—a flow of data to
	or from a file or I/O device. Streams are managed by the HP-UX operating
	system. Access to a stream is provided by a stream pointer, which is the
	address of a C-like structure that contains information about a stream.
	When the Fortran 90 intrinsic FSTREAMis given a logical unit number, it
	returns a stream pointer, providing Fortran programs with access to
	stream-based system routines.
symbol table	A table of names of procedures and data, including their offset addresses.
	The compiler inserts a symbol table in the object file for use by the debugger
	and profiler.

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