DIGITAL Fortran 90
User Manual for
DIGITAL UNIX Systems

Contents

Preface
Preface	Preface
Chapter 1
1	Getting Started
1.1	The DIGITAL Fortran 90 Programming Environment
1.2	Commands to Create and Run an Executable Program
1.3	Creating and Running a Program Using a Module and Separate Function
1.3.1	Commands to Create the Executable Program
1.3.2	Running the Sample Program
1.3.3	Debugging the Sample Program
1.4	The f90 Command and Related Software Components
1.4.1	The f90 Command Driver Program
1.4.2	cpp and Other Preprocessors
1.4.3	DIGITAL Fortran 90 Compiler
1.4.4	Other Compilers
1.4.5	Linker (ld)
1.5	Program Development Stages and Tools
Chapter 2
2	Compiling and Linking DIGITAL Fortran 90 Programs
2.1	The f90 Command: Files and Options
2.1.1	File Suffixes and Source Forms
2.1.2	Format of the f90 Command
2.1.3	Specifying Files and Options
2.1.4	Creating and Using Module Files
2.1.4.1	Creating Module Files
2.1.4.2	Using Module Files
2.1.5	The INCLUDE Statement and Using Include Files
2.1.6	Output Files: Executable, Object, and Temporary
2.1.6.1	Naming Output Files
2.1.6.2	Temporary Files
2.1.7	Using Multiple Input Files: Effect on Output Files
2.1.8	Examples of the f90 Command
2.1.8.1	Compiling and Linking Multiple Files
2.1.8.2	Retaining an Object File and Preventing Linking
2.1.8.3	Compiling Fortran 90 and C Source Files and Linking an Object File
2.1.8.4	Renaming the Output File
2.1.8.5	Specifying an Additional Linker Library
2.1.8.6	Requesting Additional Optimizations
2.1.9	Using Listing Files
2.2	Passing Options to cc and ld
2.2.1	f90 Driver Program Interaction with cc and ld
2.2.2	make Facility
2.2.3	Options Passed to the cc Driver or ld Linker
2.3	Compiler Limits, Compiler Messages, and Linker Messages
2.3.1	Compiler Limits
2.3.2	Compiler Diagnostic Messages and Error Conditions
2.3.3	Linker Diagnostic Messages and Error Conditions
2.4	Compilation Control: Statements and Directives
2.5	Specifying Object Libraries for Linking
2.5.1	Specifying Additional Object Libraries
2.5.2	Specifying Types of Object Libraries
2.5.3	Specifying Shared Object Libraries
2.6	Creating Shared Libraries
2.6.1	Creating a Shared Library with a Single f90 Command
2.6.2	Creating a Shared Library with f90 and ld Commands
2.6.3	Choosing How to Create a Shared Library
2.6.4	Shared Library Restrictions
2.6.5	Installing Shared Libraries
Chapter 3
3	f90 Command Options
3.1	f90 Command Options and Categories
3.2	-align keyword --- Data Alignment
3.3	-altparam --- Alternative PARAMETER Syntax
3.4	-arch keyword --- Specify Type of Code Instructions Generated
3.5	-assume byterecl --- Units for Unformatted File Record Length
3.6	-assume dummy_aliases --- Dummy Variable Aliasing
3.7	-assume gfullpath --- Source File Path for Debugging
3.8	-assume minus0 --- Standard Semantics for Minus Zero
3.9	-assume pthread_lock --- Thread Lock Selection for Parallel Execution
3.10	-assume source_include --- INCLUDE file search
3.11	-assume noaccuracy_sensitive, -fp_reorder --- Reorder Floating-Point Calculations
3.12	-assume nounderscore --- Underscore on External Names
3.13	-automatic, -static --- Type of Data Storage
3.14	-c --- Inhibit Linking and Retain Object File
3.15	-call_shared, -non_shared, -shared --- Shared Library Use
3.16	-check bounds, -C, -check_bounds --- Boundary Run-Time Checking
3.17	-check noformat --- Ignore Certain Format Mismatches at Run Time
3.18	-check nooutput_conversion --- Ignore Truncated Format Mismatches at Run Time
3.19	-check nopower --- Allow Special Floating-Point Expressions
3.20	-check omp_bindings --- OpenMPtm Fortran API Binding Rules Checking
3.21	-check overflow --- Integer Overflow Run-Time Checking
3.22	-check underflow --- Floating-Point Underflow Run-Time Checking
3.23	-convert keyword --- Unformatted Numeric Data Conversion
3.24	-cpp and Related Options --- Run C Preprocessor
3.24.1	-Dname and -Dname=def --- Define cpp Names
3.24.2	-I --- Remove Directory from cpp Include Search Path
3.24.3	-Idir --- Add Directory to cpp Include Search Path
3.24.4	-K --- Keep Temporary Files
3.24.5	-M --- Request cpp Dependency Lists for make
3.24.6	-P --- Retain cpp Intermediate Files
3.24.7	-Uname --- Undefine cpp Name
3.24.8	-Wp,-xxx --- Pass Specified Option to cpp
3.25	-Dname and -Dname=def --- Define Symbol Names
3.26	-d_lines --- Debugging Statement Indicator, Column 1
3.27	-double_size 128, -double_size 64 --- Double Precision Data Size
3.28	-error_limit num, -noerror_limit --- Limit Error Messages
3.29	-extend_source --- Line Length for Fixed-Format Source
3.30	-f66, -66, -nof77, -onetrip, -1 --- FORTRAN IV Compatibility
3.31	-fast --- Set Options to Improve Run-Time Performance
3.32	-feedback file, -gen_feedback, -cord --- Create and Use Feedback Files
3.33	-fixed, -free --- Fortran 90 Source Form
3.34	-fpconstant --- Handling of Floating-Point Constants
3.35	-fpen --- Control Arithmetic Exception Handling and Reporting
3.36	-fprm keyword --- Control Floating-Point Rounding Mode
3.37	-fuse_xref --- Cross-Reference Information for DEC FUSE
3.38	-g0, -g1, -g2 or -g, -g3, -ladebug --- Symbol Table Information
3.39	-granularity keyword --- Control Shared Memory Access to Data
3.40	-hpf_matmul --- Use Prior Version of MATMUL Intrinsic
3.41	-I --- Remove Directory from Include Search Path
3.42	-Idir --- Add Directory for Module and Include File Search
3.43	-i2, -i4, -i8, -integer_size num --- Integer and Logical Data Size
3.44	-inline keyword, -noinline --- Control Procedure Inlining
3.45	-intconstant --- Handling of Integer Constants
3.46	-K --- Keep Temporary Files
3.47	-L --- Remove ld Directory Search Path
3.48	-Ldir --- Add Directory to ld Search Path
3.49	-lstring --- Add Library Name to ld Search
3.50	-math_library accurate or -math_library fast --- Fast or Accurate Math Library Routines
3.51	-module directory --- Specify Directory for Creating Modules Files
3.52	-mp --- Enable Parallel Processing Using Directed Decomposition
3.53	-names keyword --- Case Control of Source and External Names
3.54	-nofor_main --- Allow Non-Fortran Main Program
3.55	-noinclude --- Omit Standard Directory Search for INCLUDE Files
3.56	-nowsf_main --- Compile HPF Global Routine for Nonparallel Main Program
3.57	-o output --- Name Output File
3.58	-O0, -O1, -O2, -O3, -O4 or -O, -O5 --- Specify Optimization Level
3.59	-om --- Request Nonshared Object Optimizations
3.60	-omp --- Enable OpenMP Parallel Processing Using Directed Decomposition
3.61	-pad_source --- Pad Short Source Records with Spaces
3.62	-pipeline --- Activate Software Pipelining Optimization
3.63	-p0, -p1 or -p, -pg, and -pprof --- Profiling Support
3.64	-pthread --- Link Using Threaded Run-Time Library
3.65	-r8 or -real_size 64, -real_size 32 --- Floating-Point Data Size
3.66	-recursive --- Request Recursive Execution
3.67	-reentrancy keyword --- Control Use of Threaded Run-Time Library
3.68	-S --- Create Assembler File
3.69	-show keyword, -machine_code --- Control Listing File Content
3.70	-speculate keyword --- Speculative Execution Optimization
3.71	-std or -std90, -std95 --- Perform Fortran 90/95 Standards Checking
3.72	-synchronous_exceptions --- Report Exceptions More Precisely
3.73	-syntax_only --- Do Not Create Object File
3.74	-threads --- Link Using Threaded Run-Time Library
3.75	-transform_loops --- Activate Loop Transformation Optimizations
3.76	-tune keyword --- Specify Alpha Processor Implementation
3.77	-Uname --- Undefine Preprocessor Symbol Name
3.78	-unroll num --- Specify Number for Loop Unroll Optimization
3.79	-V --- Create Listing File
3.80	-v --- Verbose Command Processing Display
3.81	-version --- Show DIGITAL Fortran 90 Version Information
3.82	-vms --- OpenVMS Fortran Compatibility
3.83	-Wl,-xxx --- Pass Specified Option to ld
3.84	-warn keyword, -u, -nowarn, -w, -w1 --- Warning Messages and Compiler Checking
3.85	-warning_severity keyword --- Elevate Severity of Warning Messages
3.86	-what --- Print Version Strings
3.87	-wsf, -wsf num, and Related Options --- Compile for DIGITAL Parallel Software Environment Execution
3.87.1	-assume bigarrays --- Run-time Checking for Distributed Small Array Dimensions
3.87.2	-assume nozsize --- Omit Zero-Sized Array Checking
3.87.3	-nearest_neighbor, -nearest_neighbor num, or -nonearest_neighbor --- Nearest Neighbor Optimization
3.87.4	-pprof method --- Prepare for Parallel Profiling
3.87.5	-show hpf --- Show HPF Parallelization Information