Using and Porting GNU Fortran

This manual documents how to run, install and port g77, as well as its new features and incompatibilities, and how to report bugs. It corresponds to the GCC-2.95 version of g77.

• GNU GENERAL PUBLIC LICENSE
  • Preamble
  • TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
  • How to Apply These Terms to Your New Programs
• Contributors to GNU Fortran
• 2 Funding Free Software
• 3 Funding GNU Fortran
• 4 Protect Your Freedom--Fight "Look And Feel"
• 5 Getting Started
• 6 What is GNU Fortran?
• 7 Compile Fortran, C, or Other Programs
• 8 GNU Fortran Command Options
  • 8.1 Option Summary
  • 8.2 Options Controlling the Kind of Output
  • 8.3 Shorthand Options
  • 8.4 Options Controlling Fortran Dialect
  • 8.5 Options to Request or Suppress Warnings
  • 8.6 Options for Debugging Your Program or GNU Fortran
  • 8.7 Options That Control Optimization
  • 8.8 Options Controlling the Preprocessor
  • 8.9 Options for Directory Search
  • 8.10 Options for Code Generation Conventions
  • 8.11 Environment Variables Affecting GNU Fortran
• 9 News About GNU Fortran
• 10 User-visible Changes
• 11 The GNU Fortran Language
  • 11.1 Direction of Language Development
  • 11.2 ANSI FORTRAN 77 Standard Support
    • 11.2.1 No Passing External Assumed-length
    • 11.2.2 No Passing Dummy Assumed-length
    • 11.2.3 No Pathological Implied-DO
    • 11.2.4 No Useless Implied-DO
  • 11.3 Conformance
  • 11.4 Notation Used in This Chapter
  • 11.5 Fortran Terms and Concepts
    • 11.5.1 Syntactic Items
    • 11.5.2 Statements, Comments, and Lines
    • 11.5.3 Scope of Symbolic Names and Statement Labels
  • 11.6 Characters, Lines, and Execution Sequence
    • 11.6.1 GNU Fortran Character Set
    • 11.6.2 Lines
    • 11.6.3 Continuation Line
    • 11.6.4 Statements
    • 11.6.5 Statement Labels
    • 11.6.6 Order of Statements and Lines
    • 11.6.7 Including Source Text
    • 11.6.8 Cpp-style directives
  • 11.7 Data Types and Constants
    • 11.7.1 Data Types
      • 11.7.1.1 Double Notation
      • 11.7.1.2 Star Notation
      • 11.7.1.3 Kind Notation
    • 11.7.2 Constants
    • 11.7.3 Integer Type
    • 11.7.4 Character Type
  • 11.8 Expressions
    • 11.8.1 The %LOC() Construct
  • 11.9 Specification Statements
    • 11.9.1 NAMELIST Statement
    • 11.9.2 DOUBLE COMPLEX Statement
  • 11.10 Control Statements
    • 11.10.1 DO WHILE
    • 11.10.2 END DO
    • 11.10.3 Construct Names
    • 11.10.4 The CYCLE and EXIT Statements
  • 11.11 Functions and Subroutines
    • 11.11.1 The %VAL() Construct
    • 11.11.2 The %REF() Construct
    • 11.11.3 The %DESCR() Construct
    • 11.11.4 Generics and Specifics
    • 11.11.5 REAL() and AIMAG() of Complex
    • 11.11.6 CMPLX() of DOUBLE PRECISION
    • 11.11.7 MIL-STD 1753 Support
    • 11.11.8 f77/f2c Intrinsics
    • 11.11.9 Table of Intrinsic Functions
      • 11.11.9.1 Abort Intrinsic
      • 11.11.9.2 Abs Intrinsic
      • 11.11.9.3 Access Intrinsic
      • 11.11.9.4 AChar Intrinsic
      • 11.11.9.5 ACos Intrinsic
      • 11.11.9.6 AdjustL Intrinsic
      • 11.11.9.7 AdjustR Intrinsic
      • 11.11.9.8 AImag Intrinsic
      • 11.11.9.9 AInt Intrinsic
      • 11.11.9.10 Alarm Intrinsic
      • 11.11.9.11 All Intrinsic
      • 11.11.9.12 Allocated Intrinsic
      • 11.11.9.13 ALog Intrinsic
      • 11.11.9.14 ALog10 Intrinsic
      • 11.11.9.15 AMax0 Intrinsic
      • 11.11.9.16 AMax1 Intrinsic
      • 11.11.9.17 AMin0 Intrinsic
      • 11.11.9.18 AMin1 Intrinsic
      • 11.11.9.19 AMod Intrinsic
      • 11.11.9.20 And Intrinsic
      • 11.11.9.21 ANInt Intrinsic
      • 11.11.9.22 Any Intrinsic
      • 11.11.9.23 ASin Intrinsic
      • 11.11.9.24 Associated Intrinsic
      • 11.11.9.25 ATan Intrinsic
      • 11.11.9.26 ATan2 Intrinsic
      • 11.11.9.27 BesJ0 Intrinsic
      • 11.11.9.28 BesJ1 Intrinsic
      • 11.11.9.29 BesJN Intrinsic
      • 11.11.9.30 BesY0 Intrinsic
      • 11.11.9.31 BesY1 Intrinsic
      • 11.11.9.32 BesYN Intrinsic
      • 11.11.9.33 Bit_Size Intrinsic
      • 11.11.9.34 BTest Intrinsic
      • 11.11.9.35 CAbs Intrinsic
      • 11.11.9.36 CCos Intrinsic
      • 11.11.9.37 Ceiling Intrinsic
      • 11.11.9.38 CExp Intrinsic
      • 11.11.9.39 Char Intrinsic
      • 11.11.9.40 ChDir Intrinsic (subroutine)
      • 11.11.9.41 ChMod Intrinsic (subroutine)
      • 11.11.9.42 CLog Intrinsic
      • 11.11.9.43 Cmplx Intrinsic
      • 11.11.9.44 Complex Intrinsic
      • 11.11.9.45 Conjg Intrinsic
      • 11.11.9.46 Cos Intrinsic
      • 11.11.9.47 CosH Intrinsic
      • 11.11.9.48 Count Intrinsic
      • 11.11.9.49 CPU_Time Intrinsic
      • 11.11.9.50 CShift Intrinsic
      • 11.11.9.51 CSin Intrinsic
      • 11.11.9.52 CSqRt Intrinsic
      • 11.11.9.53 CTime Intrinsic (subroutine)
      • 11.11.9.54 CTime Intrinsic (function)
      • 11.11.9.55 DAbs Intrinsic
      • 11.11.9.56 DACos Intrinsic
      • 11.11.9.57 DASin Intrinsic
      • 11.11.9.58 DATan Intrinsic
      • 11.11.9.59 DATan2 Intrinsic
      • 11.11.9.60 Date_and_Time Intrinsic
      • 11.11.9.61 DbesJ0 Intrinsic
      • 11.11.9.62 DbesJ1 Intrinsic
      • 11.11.9.63 DbesJN Intrinsic
      • 11.11.9.64 DbesY0 Intrinsic
      • 11.11.9.65 DbesY1 Intrinsic
      • 11.11.9.66 DbesYN Intrinsic
      • 11.11.9.67 Dble Intrinsic
      • 11.11.9.68 DCos Intrinsic
      • 11.11.9.69 DCosH Intrinsic
      • 11.11.9.70 DDiM Intrinsic
      • 11.11.9.71 DErF Intrinsic
      • 11.11.9.72 DErFC Intrinsic
      • 11.11.9.73 DExp Intrinsic
      • 11.11.9.74 Digits Intrinsic
      • 11.11.9.75 DiM Intrinsic
      • 11.11.9.76 DInt Intrinsic
      • 11.11.9.77 DLog Intrinsic
      • 11.11.9.78 DLog10 Intrinsic
      • 11.11.9.79 DMax1 Intrinsic
      • 11.11.9.80 DMin1 Intrinsic
      • 11.11.9.81 DMod Intrinsic
      • 11.11.9.82 DNInt Intrinsic
      • 11.11.9.83 Dot_Product Intrinsic
      • 11.11.9.84 DProd Intrinsic
      • 11.11.9.85 DSign Intrinsic
      • 11.11.9.86 DSin Intrinsic
      • 11.11.9.87 DSinH Intrinsic
      • 11.11.9.88 DSqRt Intrinsic
      • 11.11.9.89 DTan Intrinsic
      • 11.11.9.90 DTanH Intrinsic
      • 11.11.9.91 DTime Intrinsic (subroutine)
      • 11.11.9.92 EOShift Intrinsic
      • 11.11.9.93 Epsilon Intrinsic
      • 11.11.9.94 ErF Intrinsic
      • 11.11.9.95 ErFC Intrinsic
      • 11.11.9.96 ETime Intrinsic (subroutine)
      • 11.11.9.97 ETime Intrinsic (function)
      • 11.11.9.98 Exit Intrinsic
      • 11.11.9.99 Exp Intrinsic
      • 11.11.9.100 Exponent Intrinsic
      • 11.11.9.101 FDate Intrinsic (subroutine)
      • 11.11.9.102 FDate Intrinsic (function)
      • 11.11.9.103 FGet Intrinsic (subroutine)
      • 11.11.9.104 FGetC Intrinsic (subroutine)
      • 11.11.9.105 Float Intrinsic
      • 11.11.9.106 Floor Intrinsic
      • 11.11.9.107 Flush Intrinsic
      • 11.11.9.108 FNum Intrinsic
      • 11.11.9.109 FPut Intrinsic (subroutine)
      • 11.11.9.110 FPutC Intrinsic (subroutine)
      • 11.11.9.111 Fraction Intrinsic
      • 11.11.9.112 FSeek Intrinsic
      • 11.11.9.113 FStat Intrinsic (subroutine)
      • 11.11.9.114 FStat Intrinsic (function)
      • 11.11.9.115 FTell Intrinsic (subroutine)
      • 11.11.9.116 FTell Intrinsic (function)
      • 11.11.9.117 GError Intrinsic
      • 11.11.9.118 GetArg Intrinsic
      • 11.11.9.119 GetCWD Intrinsic (subroutine)
      • 11.11.9.120 GetCWD Intrinsic (function)
      • 11.11.9.121 GetEnv Intrinsic
      • 11.11.9.122 GetGId Intrinsic
      • 11.11.9.123 GetLog Intrinsic
      • 11.11.9.124 GetPId Intrinsic
      • 11.11.9.125 GetUId Intrinsic
      • 11.11.9.126 GMTime Intrinsic
      • 11.11.9.127 HostNm Intrinsic (subroutine)
      • 11.11.9.128 HostNm Intrinsic (function)
      • 11.11.9.129 Huge Intrinsic
      • 11.11.9.130 IAbs Intrinsic
      • 11.11.9.131 IAChar Intrinsic
      • 11.11.9.132 IAnd Intrinsic
      • 11.11.9.133 IArgC Intrinsic
      • 11.11.9.134 IBClr Intrinsic
      • 11.11.9.135 IBits Intrinsic
      • 11.11.9.136 IBSet Intrinsic
      • 11.11.9.137 IChar Intrinsic
      • 11.11.9.138 IDate Intrinsic (UNIX)
      • 11.11.9.139 IDiM Intrinsic
      • 11.11.9.140 IDInt Intrinsic
      • 11.11.9.141 IDNInt Intrinsic
      • 11.11.9.142 IEOr Intrinsic
      • 11.11.9.143 IErrNo Intrinsic
      • 11.11.9.144 IFix Intrinsic
      • 11.11.9.145 Imag Intrinsic
      • 11.11.9.146 ImagPart Intrinsic
      • 11.11.9.147 Index Intrinsic
      • 11.11.9.148 Int Intrinsic
      • 11.11.9.149 Int2 Intrinsic
      • 11.11.9.150 Int8 Intrinsic
      • 11.11.9.151 IOr Intrinsic
      • 11.11.9.152 IRand Intrinsic
      • 11.11.9.153 IsaTty Intrinsic
      • 11.11.9.154 IShft Intrinsic
      • 11.11.9.155 IShftC Intrinsic
      • 11.11.9.156 ISign Intrinsic
      • 11.11.9.157 ITime Intrinsic
      • 11.11.9.158 Kill Intrinsic (subroutine)
      • 11.11.9.159 Kind Intrinsic
      • 11.11.9.160 LBound Intrinsic
      • 11.11.9.161 Len Intrinsic
      • 11.11.9.162 Len_Trim Intrinsic
      • 11.11.9.163 LGe Intrinsic
      • 11.11.9.164 LGt Intrinsic
      • 11.11.9.165 Link Intrinsic (subroutine)
      • 11.11.9.166 LLe Intrinsic
      • 11.11.9.167 LLt Intrinsic
      • 11.11.9.168 LnBlnk Intrinsic
      • 11.11.9.169 Loc Intrinsic
      • 11.11.9.170 Log Intrinsic
      • 11.11.9.171 Log10 Intrinsic
      • 11.11.9.172 Logical Intrinsic
      • 11.11.9.173 Long Intrinsic
      • 11.11.9.174 LShift Intrinsic
      • 11.11.9.175 LStat Intrinsic (subroutine)
      • 11.11.9.176 LStat Intrinsic (function)
      • 11.11.9.177 LTime Intrinsic
      • 11.11.9.178 MatMul Intrinsic
      • 11.11.9.179 Max Intrinsic
      • 11.11.9.180 Max0 Intrinsic
      • 11.11.9.181 Max1 Intrinsic
      • 11.11.9.182 MaxExponent Intrinsic
      • 11.11.9.183 MaxLoc Intrinsic
      • 11.11.9.184 MaxVal Intrinsic
      • 11.11.9.185 MClock Intrinsic
      • 11.11.9.186 MClock8 Intrinsic
      • 11.11.9.187 Merge Intrinsic
      • 11.11.9.188 Min Intrinsic
      • 11.11.9.189 Min0 Intrinsic
      • 11.11.9.190 Min1 Intrinsic
      • 11.11.9.191 MinExponent Intrinsic
      • 11.11.9.192 MinLoc Intrinsic
      • 11.11.9.193 MinVal Intrinsic
      • 11.11.9.194 Mod Intrinsic
      • 11.11.9.195 Modulo Intrinsic
      • 11.11.9.196 MvBits Intrinsic
      • 11.11.9.197 Nearest Intrinsic
      • 11.11.9.198 NInt Intrinsic
      • 11.11.9.199 Not Intrinsic
      • 11.11.9.200 Or Intrinsic
      • 11.11.9.201 Pack Intrinsic
      • 11.11.9.202 PError Intrinsic
      • 11.11.9.203 Precision Intrinsic
      • 11.11.9.204 Present Intrinsic
      • 11.11.9.205 Product Intrinsic
      • 11.11.9.206 Radix Intrinsic
      • 11.11.9.207 Rand Intrinsic
      • 11.11.9.208 Random_Number Intrinsic
      • 11.11.9.209 Random_Seed Intrinsic
      • 11.11.9.210 Range Intrinsic
      • 11.11.9.211 Real Intrinsic
      • 11.11.9.212 RealPart Intrinsic
      • 11.11.9.213 Rename Intrinsic (subroutine)
      • 11.11.9.214 Repeat Intrinsic
      • 11.11.9.215 Reshape Intrinsic
      • 11.11.9.216 RRSpacing Intrinsic
      • 11.11.9.217 RShift Intrinsic
      • 11.11.9.218 Scale Intrinsic
      • 11.11.9.219 Scan Intrinsic
      • 11.11.9.220 Second Intrinsic (function)
      • 11.11.9.221 Second Intrinsic (subroutine)
      • 11.11.9.222 Selected_Int_Kind Intrinsic
      • 11.11.9.223 Selected_Real_Kind Intrinsic
      • 11.11.9.224 Set_Exponent Intrinsic
      • 11.11.9.225 Shape Intrinsic
      • 11.11.9.226 Short Intrinsic
      • 11.11.9.227 Sign Intrinsic
      • 11.11.9.228 Signal Intrinsic (subroutine)
      • 11.11.9.229 Sin Intrinsic
      • 11.11.9.230 SinH Intrinsic
      • 11.11.9.231 Sleep Intrinsic
      • 11.11.9.232 Sngl Intrinsic
      • 11.11.9.233 Spacing Intrinsic
      • 11.11.9.234 Spread Intrinsic
      • 11.11.9.235 SqRt Intrinsic
      • 11.11.9.236 SRand Intrinsic
      • 11.11.9.237 Stat Intrinsic (subroutine)
      • 11.11.9.238 Stat Intrinsic (function)
      • 11.11.9.239 Sum Intrinsic
      • 11.11.9.240 SymLnk Intrinsic (subroutine)
      • 11.11.9.241 System Intrinsic (subroutine)
      • 11.11.9.242 System_Clock Intrinsic
      • 11.11.9.243 Tan Intrinsic
      • 11.11.9.244 TanH Intrinsic
      • 11.11.9.245 Time Intrinsic (UNIX)
      • 11.11.9.246 Time8 Intrinsic
      • 11.11.9.247 Tiny Intrinsic
      • 11.11.9.248 Transfer Intrinsic
      • 11.11.9.249 Transpose Intrinsic
      • 11.11.9.250 Trim Intrinsic
      • 11.11.9.251 TtyNam Intrinsic (subroutine)
      • 11.11.9.252 TtyNam Intrinsic (function)
      • 11.11.9.253 UBound Intrinsic
      • 11.11.9.254 UMask Intrinsic (subroutine)
      • 11.11.9.255 Unlink Intrinsic (subroutine)
      • 11.11.9.256 Unpack Intrinsic
      • 11.11.9.257 Verify Intrinsic
      • 11.11.9.258 XOr Intrinsic
      • 11.11.9.259 ZAbs Intrinsic
      • 11.11.9.260 ZCos Intrinsic
      • 11.11.9.261 ZExp Intrinsic
      • 11.11.9.262 ZLog Intrinsic
      • 11.11.9.263 ZSin Intrinsic
      • 11.11.9.264 ZSqRt Intrinsic
  • 11.12 Scope and Classes of Symbolic Names
    • 11.12.1 Underscores in Symbol Names
  • 11.13 I/O
  • 11.14 Fortran 90 Features
• 12 Other Dialects
  • 12.1 Source Form
    • 12.1.1 Carriage Returns
    • 12.1.2 Tabs
    • 12.1.3 Short Lines
    • 12.1.4 Long Lines
    • 12.1.5 Ampersand Continuation Line
  • 12.2 Trailing Comment
  • 12.3 Debug Line
  • 12.4 Dollar Signs in Symbol Names
  • 12.5 Case Sensitivity
  • 12.6 VXT Fortran
    • 12.6.1 Meaning of Double Quote
    • 12.6.2 Meaning of Exclamation Point in Column 6
  • 12.7 Fortran 90
  • 12.8 Pedantic Compilation
  • 12.9 Distensions
    • 12.9.1 Implicit Argument Conversion
    • 12.9.2 Ugly Assumed-Size Arrays
    • 12.9.3 Ugly Complex Part Extraction
    • 12.9.4 Ugly Null Arguments
    • 12.9.5 Ugly Conversion of Initializers
    • 12.9.6 Ugly Integer Conversions
    • 12.9.7 Ugly Assigned Labels
• 13 The GNU Fortran Compiler
  • 13.1 Compiler Limits
  • 13.2 Run-time Environment Limits
    • 13.2.1 Timer Wraparounds
    • 13.2.2 Year 2000 (Y2K) Problems
    • 13.2.3 Array Size
    • 13.2.4 Character-variable Length
    • 13.2.5 Year 10000 (Y10K) Problems
  • 13.3 Compiler Types
  • 13.4 Compiler Constants
  • 13.5 Compiler Intrinsics
    • 13.5.1 Intrinsic Groups
    • 13.5.2 Other Intrinsics
      • 13.5.2.1 ACosD Intrinsic
      • 13.5.2.2 AIMax0 Intrinsic
      • 13.5.2.3 AIMin0 Intrinsic
      • 13.5.2.4 AJMax0 Intrinsic
      • 13.5.2.5 AJMin0 Intrinsic
      • 13.5.2.6 ASinD Intrinsic
      • 13.5.2.7 ATan2D Intrinsic
      • 13.5.2.8 ATanD Intrinsic
      • 13.5.2.9 BITest Intrinsic
      • 13.5.2.10 BJTest Intrinsic
      • 13.5.2.11 CDAbs Intrinsic
      • 13.5.2.12 CDCos Intrinsic
      • 13.5.2.13 CDExp Intrinsic
      • 13.5.2.14 CDLog Intrinsic
      • 13.5.2.15 CDSin Intrinsic
      • 13.5.2.16 CDSqRt Intrinsic
      • 13.5.2.17 ChDir Intrinsic (function)
      • 13.5.2.18 ChMod Intrinsic (function)
      • 13.5.2.19 CosD Intrinsic
      • 13.5.2.20 DACosD Intrinsic
      • 13.5.2.21 DASinD Intrinsic
      • 13.5.2.22 DATan2D Intrinsic
      • 13.5.2.23 DATanD Intrinsic
      • 13.5.2.24 Date Intrinsic
      • 13.5.2.25 DbleQ Intrinsic
      • 13.5.2.26 DCmplx Intrinsic
      • 13.5.2.27 DConjg Intrinsic
      • 13.5.2.28 DCosD Intrinsic
      • 13.5.2.29 DFloat Intrinsic
      • 13.5.2.30 DFlotI Intrinsic
      • 13.5.2.31 DFlotJ Intrinsic
      • 13.5.2.32 DImag Intrinsic
      • 13.5.2.33 DReal Intrinsic
      • 13.5.2.34 DSinD Intrinsic
      • 13.5.2.35 DTanD Intrinsic
      • 13.5.2.36 DTime Intrinsic (function)
      • 13.5.2.37 FGet Intrinsic (function)
      • 13.5.2.38 FGetC Intrinsic (function)
      • 13.5.2.39 FloatI Intrinsic
      • 13.5.2.40 FloatJ Intrinsic
      • 13.5.2.41 FPut Intrinsic (function)
      • 13.5.2.42 FPutC Intrinsic (function)
      • 13.5.2.43 IDate Intrinsic (VXT)
      • 13.5.2.44 IIAbs Intrinsic
      • 13.5.2.45 IIAnd Intrinsic
      • 13.5.2.46 IIBClr Intrinsic
      • 13.5.2.47 IIBits Intrinsic
      • 13.5.2.48 IIBSet Intrinsic
      • 13.5.2.49 IIDiM Intrinsic
      • 13.5.2.50 IIDInt Intrinsic
      • 13.5.2.51 IIDNnt Intrinsic
      • 13.5.2.52 IIEOr Intrinsic
      • 13.5.2.53 IIFix Intrinsic
      • 13.5.2.54 IInt Intrinsic
      • 13.5.2.55 IIOr Intrinsic
      • 13.5.2.56 IIQint Intrinsic
      • 13.5.2.57 IIQNnt Intrinsic
      • 13.5.2.58 IIShftC Intrinsic
      • 13.5.2.59 IISign Intrinsic
      • 13.5.2.60 IMax0 Intrinsic
      • 13.5.2.61 IMax1 Intrinsic
      • 13.5.2.62 IMin0 Intrinsic
      • 13.5.2.63 IMin1 Intrinsic
      • 13.5.2.64 IMod Intrinsic
      • 13.5.2.65 INInt Intrinsic
      • 13.5.2.66 INot Intrinsic
      • 13.5.2.67 IZExt Intrinsic
      • 13.5.2.68 JIAbs Intrinsic
      • 13.5.2.69 JIAnd Intrinsic
      • 13.5.2.70 JIBClr Intrinsic
      • 13.5.2.71 JIBits Intrinsic
      • 13.5.2.72 JIBSet Intrinsic
      • 13.5.2.73 JIDiM Intrinsic
      • 13.5.2.74 JIDInt Intrinsic
      • 13.5.2.75 JIDNnt Intrinsic
      • 13.5.2.76 JIEOr Intrinsic
      • 13.5.2.77 JIFix Intrinsic
      • 13.5.2.78 JInt Intrinsic
      • 13.5.2.79 JIOr Intrinsic
      • 13.5.2.80 JIQint Intrinsic
      • 13.5.2.81 JIQNnt Intrinsic
      • 13.5.2.82 JIShft Intrinsic
      • 13.5.2.83 JIShftC Intrinsic
      • 13.5.2.84 JISign Intrinsic
      • 13.5.2.85 JMax0 Intrinsic
      • 13.5.2.86 JMax1 Intrinsic
      • 13.5.2.87 JMin0 Intrinsic
      • 13.5.2.88 JMin1 Intrinsic
      • 13.5.2.89 JMod Intrinsic
      • 13.5.2.90 JNInt Intrinsic
      • 13.5.2.91 JNot Intrinsic
      • 13.5.2.92 JZExt Intrinsic
      • 13.5.2.93 Kill Intrinsic (function)
      • 13.5.2.94 Link Intrinsic (function)
      • 13.5.2.95 QAbs Intrinsic
      • 13.5.2.96 QACos Intrinsic
      • 13.5.2.97 QACosD Intrinsic
      • 13.5.2.98 QASin Intrinsic
      • 13.5.2.99 QASinD Intrinsic
      • 13.5.2.100 QATan Intrinsic
      • 13.5.2.101 QATan2 Intrinsic
      • 13.5.2.102 QATan2D Intrinsic
      • 13.5.2.103 QATanD Intrinsic
      • 13.5.2.104 QCos Intrinsic
      • 13.5.2.105 QCosD Intrinsic
      • 13.5.2.106 QCosH Intrinsic
      • 13.5.2.107 QDiM Intrinsic
      • 13.5.2.108 QExp Intrinsic
      • 13.5.2.109 QExt Intrinsic
      • 13.5.2.110 QExtD Intrinsic
      • 13.5.2.111 QFloat Intrinsic
      • 13.5.2.112 QInt Intrinsic
      • 13.5.2.113 QLog Intrinsic
      • 13.5.2.114 QLog10 Intrinsic
      • 13.5.2.115 QMax1 Intrinsic
      • 13.5.2.116 QMin1 Intrinsic
      • 13.5.2.117 QMod Intrinsic
      • 13.5.2.118 QNInt Intrinsic
      • 13.5.2.119 QSin Intrinsic
      • 13.5.2.120 QSinD Intrinsic
      • 13.5.2.121 QSinH Intrinsic
      • 13.5.2.122 QSqRt Intrinsic
      • 13.5.2.123 QTan Intrinsic
      • 13.5.2.124 QTanD Intrinsic
      • 13.5.2.125 QTanH Intrinsic
      • 13.5.2.126 Rename Intrinsic (function)
      • 13.5.2.127 Secnds Intrinsic
      • 13.5.2.128 Signal Intrinsic (function)
      • 13.5.2.129 SinD Intrinsic
      • 13.5.2.130 SnglQ Intrinsic
      • 13.5.2.131 SymLnk Intrinsic (function)
      • 13.5.2.132 System Intrinsic (function)
      • 13.5.2.133 TanD Intrinsic
      • 13.5.2.134 Time Intrinsic (VXT)
      • 13.5.2.135 UMask Intrinsic (function)
      • 13.5.2.136 Unlink Intrinsic (function)
      • 13.5.2.137 ZExt Intrinsic
• 14 Other Compilers
  • 14.1 Dropping f2c Compatibility
  • 14.2 Compilers Other Than f2c
• 15 Other Languages
  • 15.1 Tools and advice for interoperating with C and C++
    • 15.1.1 C Interfacing Tools
    • 15.1.2 Accessing Type Information in C
    • 15.1.3 Generating Skeletons and Prototypes with f2c
    • 15.1.4 C++ Considerations
    • 15.1.5 Startup Code
• 16 Installing GNU Fortran
  • 16.1 Prerequisites
  • 16.2 Problems Installing
    • 16.2.1 General Problems
      • 16.2.1.1 GNU C Required
      • 16.2.1.2 Patching GNU CC
      • 16.2.1.3 Building GNU CC Necessary
      • 16.2.1.4 Missing strtoul or bsearch
      • 16.2.1.5 Cleanup Kills Stage Directories
      • 16.2.1.6 LANGUAGES Macro Ignored
    • 16.2.2 System-specific Problems
    • 16.2.3 Cross-compiler Problems
  • 16.3 Changing Settings Before Building
    • 16.3.1 Larger File Unit Numbers
    • 16.3.2 Always Flush Output
    • 16.3.3 Maximum Stackable Size
    • 16.3.4 Floating-point Bit Patterns
    • 16.3.5 Initialization of Large Aggregate Areas
    • 16.3.6 Alpha Problems Fixed
  • 16.4 Quick Start
  • 16.5 Complete Installation
  • 16.6 Distributing Binaries
• 17 Debugging and Interfacing
  • 17.1 Main Program Unit (PROGRAM)
  • 17.2 Procedures (SUBROUTINE and FUNCTION)
  • 17.3 Functions (FUNCTION and RETURN)
  • 17.4 Names
  • 17.5 Common Blocks (COMMON)
  • 17.6 Local Equivalence Areas (EQUIVALENCE)
  • 17.7 Complex Variables (COMPLEX)
  • 17.8 Arrays (DIMENSION)
  • 17.9 Adjustable Arrays (DIMENSION)
  • 17.10 Alternate Entry Points (ENTRY)
  • 17.11 Alternate Returns (SUBROUTINE and RETURN)
  • 17.12 Assigned Statement Labels (ASSIGN and GOTO)
  • 17.13 Run-time Library Errors
• 18 Collected Fortran Wisdom
  • 18.1 Advantages Over f2c
    • 18.1.1 Language Extensions
    • 18.1.2 Diagnostic Abilities
    • 18.1.3 Compiler Options
    • 18.1.4 Compiler Speed
    • 18.1.5 Program Speed
    • 18.1.6 Ease of Debugging
    • 18.1.7 Character and Hollerith Constants
  • 18.2 Block Data and Libraries
  • 18.3 Loops
  • 18.4 Working Programs
    • 18.4.1 Not My Type
    • 18.4.2 Variables Assumed To Be Zero
    • 18.4.3 Variables Assumed To Be Saved
    • 18.4.4 Unwanted Variables
    • 18.4.5 Unused Arguments
    • 18.4.6 Surprising Interpretations of Code
    • 18.4.7 Aliasing Assumed To Work
    • 18.4.8 Output Assumed To Flush
    • 18.4.9 Large File Unit Numbers
    • 18.4.10 Floating-point precision
    • 18.4.11 Inconsistent Calling Sequences
  • 18.5 Overly Convenient Command-line Options
  • 18.6 Faster Programs
    • 18.6.1 Aligned Data
    • 18.6.2 Prefer Automatic Uninitialized Variables
    • 18.6.3 Avoid f2c Compatibility
    • 18.6.4 Use Submodel Options
• 19 Known Causes of Trouble with GNU Fortran
  • 19.1 Bugs Not In GNU Fortran
    • 19.1.1 Signal 11 and Friends
    • 19.1.2 Cannot Link Fortran Programs
    • 19.1.3 Large Common Blocks
    • 19.1.4 Debugger Problems
    • 19.1.5 NeXTStep Problems
    • 19.1.6 Stack Overflow
    • 19.1.7 Nothing Happens
    • 19.1.8 Strange Behavior at Run Time
    • 19.1.9 Floating-point Errors
  • 19.2 Known Bugs In GNU Fortran
  • 19.3 Missing Features
    • 19.3.1 Better Source Model
    • 19.3.2 Fortran 90 Support
    • 19.3.3 Intrinsics in PARAMETER Statements
    • 19.3.4 Arbitrary Concatenation
    • 19.3.5 SELECT CASE on CHARACTER Type
    • 19.3.6 RECURSIVE Keyword
    • 19.3.7 Increasing Precision/Range
    • 19.3.8 Popular Non-standard Types
    • 19.3.9 Full Support for Compiler Types
    • 19.3.10 Array Bounds Expressions
    • 19.3.11 POINTER Statements
    • 19.3.12 Sensible Non-standard Constructs
    • 19.3.13 READONLY Keyword
    • 19.3.14 FLUSH Statement
    • 19.3.15 Expressions in FORMAT Statements
    • 19.3.16 Explicit Assembler Code
    • 19.3.17 Q Edit Descriptor
    • 19.3.18 Old-style PARAMETER Statements
    • 19.3.19 TYPE and ACCEPT I/O Statements
    • 19.3.20 STRUCTURE, UNION, RECORD, MAP
    • 19.3.21 OPEN, CLOSE, and INQUIRE Keywords
    • 19.3.22 ENCODE and DECODE
    • 19.3.23 AUTOMATIC Statement
    • 19.3.24 Suppressing Space Padding of Source Lines
    • 19.3.25 Fortran Preprocessor
    • 19.3.26 Bit Operations on Floating-point Data
    • 19.3.27 Really Ugly Character Assignments
    • 19.3.28 POSIX Standard
    • 19.3.29 Floating-point Exception Handling
    • 19.3.30 Nonportable Conversions
    • 19.3.31 Large Automatic Arrays
    • 19.3.32 Support for Threads
    • 19.3.33 Enabling Debug Lines
    • 19.3.34 Better Warnings
    • 19.3.35 Gracefully Handle Sensible Bad Code
    • 19.3.36 Non-standard Conversions
    • 19.3.37 Non-standard Intrinsics
    • 19.3.38 Modifying DO Variable
    • 19.3.39 Better Pedantic Compilation
    • 19.3.40 Warn About Implicit Conversions
    • 19.3.41 Invalid Use of Hollerith Constant
    • 19.3.42 Dummy Array Without Dimensioning Dummy
    • 19.3.43 Invalid FORMAT Specifiers
    • 19.3.44 Ambiguous Dialects
    • 19.3.45 Unused Labels
    • 19.3.46 Informational Messages
    • 19.3.47 Uninitialized Variables at Run Time
    • 19.3.48 Portable Unformatted Files
    • 19.3.49 Better List-directed I/O
    • 19.3.50 Default to Console I/O
    • 19.3.51 Labels Visible to Debugger
  • 19.4 Disappointments and Misunderstandings
    • 19.4.1 Mangling of Names in Source Code
    • 19.4.2 Multiple Definitions of External Names
    • 19.4.3 Limitation on Implicit Declarations
  • 19.5 Certain Changes We Don't Want to Make
    • 19.5.1 Backslash in Constants
    • 19.5.2 Initializing Before Specifying
    • 19.5.3 Context-Sensitive Intrinsicness
    • 19.5.4 Context-Sensitive Constants
    • 19.5.5 Equivalence Versus Equality
    • 19.5.6 Order of Side Effects
  • 19.6 Warning Messages and Error Messages
• 20 Open Questions
• 21 Reporting Bugs
  • 21.1 Have You Found a Bug?
  • 21.2 Where to Report Bugs
  • 21.3 How to Report Bugs
  • 21.4 Sending Patches for GNU Fortran
• 22 How To Get Help with GNU Fortran
• 23 Adding Options
• 24 Projects
  • 24.1 Improve Efficiency
  • 24.2 Better Optimization
  • 24.3 Simplify Porting
  • 24.4 More Extensions
  • 24.5 Machine Model
  • 24.6 Internals Documentation
  • 24.7 Internals Improvements
  • 24.8 Better Diagnostics
• 25 Front End
  • 25.1 Overview of Sources
  • 25.2 Overview of Translation Process
    • 25.2.1 g77stripcard
    • 25.2.2 lex.c
    • 25.2.3 sta.c
    • 25.2.4 stb.c
    • 25.2.5 expr.c
    • 25.2.6 stc.c
    • 25.2.7 std.c
    • 25.2.8 ste.c
    • 25.2.9 Gotchas (Transforming)
      • 25.2.9.1 Multi-character Lexemes
      • 25.2.9.2 Space-padding Lexemes
      • 25.2.9.3 Bizarre Free-form Hollerith Constants
      • 25.2.9.4 Hollerith Constants
      • 25.2.9.5 Confusing Function Keyword
      • 25.2.9.6 Weird READ
    • 25.2.10 TBD (Transforming)
  • 25.3 Philosophy of Code Generation
  • 25.4 Two-pass Design
    • 25.4.1 Two-pass Code
    • 25.4.2 Why Two Passes
  • 25.5 Challenges Posed
  • 25.6 Transforming Statements
    • 25.6.1 Statements Needing Temporaries
    • 25.6.2 Transforming DO WHILE
    • 25.6.3 Transforming Iterative DO
    • 25.6.4 Transforming Block IF
    • 25.6.5 Transforming SELECT CASE
  • 25.7 Transforming Expressions
  • 25.8 Internal Naming Conventions
• 26 Diagnostics
  • 26.1 CMPAMBIG
  • 26.2 EXPIMP
  • 26.3 INTGLOB
  • 26.4 LEX
  • 26.5 GLOBALS
  • 26.6 LINKFAIL
  • 26.7 Y2KBAD
• Index

This document was generated on 7 June 2000 using the texi2html translator version 1.51a.