FYI : doc-compilers

[Akim Demaille]

Index: ChangeLog
from  Akim Demaille  <address@hidden>

        * doc/autoconf.texi (C Compiler, Fortran 77 Compiler): Be subsections
        of...
        (Generic Compiler Characteristics): this.
        (C++ Compiler): New subsection.

Index: doc/autoconf.texi
--- doc/autoconf.texi Thu, 12 Jul 2001 19:43:43 +0200 akim (ace/16_autoconf.t 
1.61.2.112.1.3 644)
+++ doc/autoconf.texi Thu, 12 Jul 2001 23:11:16 +0200 akim (ace/16_autoconf.t 
1.61.2.112.1.3 644)
@@ -217,8 +217,6 @@ @node Top, Introduction, (dir), (dir)
 * Structures::                  Structures or members that might be missing
 * Types::                       Types that might be missing
 * Compilers and Preprocessors::  Checking for compiling programs
-* C Compiler::                  Checking its characteristics
-* Fortran 77 Compiler::         Checking its characteristics
 * System Services::             Operating system services
 * UNIX Variants::               Special kludges for specific UNIX variants

@@ -258,6 +256,13 @@ @node Top, Introduction, (dir), (dir)
 * Particular Types::            Special handling to find certain types
 * Generic Types::               How to find other types

+Compilers and Preprocessors
+
+* Generic Compiler Characteristics::  Language independent tests
+* C Compiler::                  Checking its characteristics
+* C++ Compiler::                Likewise
+* Fortran 77 Compiler::         Likewise
+
 Writing Tests

 * Examining Declarations::      Detecting header files and declarations
@@ -1767,7 +1772,7 @@ @node Configuration Files, Makefile Subs
 Make @code{AC_OUTPUT} create each @address@hidden by copying an input
 file (by default @address@hidden), substituting the output variable
 values.
address@hidden FIXME: Before we used to have this feature, which was later 
rejected
address@hidden Before we used to have this feature, which was later rejected
 @c because it complicates the write of Makefiles:
 @c If the file would be unchanged, it is left untouched, to preserve
 @c timestamp.
@@ -2734,8 +2739,6 @@ @node Existing Tests, Writing Tests, Set
 * Structures::                  Structures or members that might be missing
 * Types::                       Types that might be missing
 * Compilers and Preprocessors::  Checking for compiling programs
-* C Compiler::                  Checking its characteristics
-* Fortran 77 Compiler::         Checking its characteristics
 * System Services::             Operating system services
 * UNIX Variants::               Special kludges for specific UNIX variants
 @end menu
@@ -4320,7 +4323,7 @@ @node Generic Types,  , Particular Types
 @code{AC_CHECK_TYPE}, see @ref{Obsolete Macros}.


address@hidden Compilers and Preprocessors, C Compiler, Types, Existing Tests
address@hidden Compilers and Preprocessors, System Services, Types, Existing 
Tests
 @section Compilers and Preprocessors

 @ovindex EXEEXT
@@ -4339,6 +4342,41 @@ @node Compilers and Preprocessors, C Com
 fail too.  @xref{Manual Configuration}, for more on support for cross
 compiling.

address@hidden
+* Generic Compiler Characteristics::  Language independent tests
+* C Compiler::                  Checking its characteristics
+* C++ Compiler::                Likewise
+* Fortran 77 Compiler::         Likewise
address@hidden menu
+
address@hidden Generic Compiler Characteristics, C Compiler, Compilers and 
Preprocessors, Compilers and Preprocessors
address@hidden Generic Compiler Characteristics
+
address@hidden AC_CHECK_SIZEOF (@var{type}, @ovar{unused}, @ovar{includes})
address@hidden CHECK_SIZEOF
+Define @address@hidden (@pxref{Standard Symbols}) to be the
+size in bytes of @var{type}.  If @samp{type} is unknown, it gets a size
+of 0.  If no @var{includes} are specified, the default includes are used
+(@pxref{Default Includes}).  If you provide @var{include}, make sure to
+include @file{stdio.h} which is required for this macro to run.
+
+This macro now works even when cross-compiling.  The @var{unused}
+argument was used when cross-compiling.
+
+For example, the call
+
address@hidden
+AC_CHECK_SIZEOF(int *)
address@hidden example
+
address@hidden
+defines @code{SIZEOF_INT_P} to be 8 on DEC Alpha AXP systems.
address@hidden defmac
+
+
address@hidden C Compiler, C++ Compiler, Generic Compiler Characteristics, 
Compilers and Preprocessors
address@hidden C Compiler Characteristics
+
 @defmac AC_PROG_CC (@ovar{compiler-search-list})
 @maindex PROG_CC
 @ovindex CC
@@ -4412,107 +4450,6 @@ @node Compilers and Preprocessors, C Com
 consider the test failed if any warnings have been reported.
 @end defmac

address@hidden AC_PROG_CXX (@ovar{compiler-search-list})
address@hidden PROG_CXX
address@hidden CXX
address@hidden CXXFLAGS
-Determine a C++ compiler to use.  Check if the environment variable
address@hidden or @code{CCC} (in that order) is set; if so, then set output
-variable @code{CXX} to its value.
-
-Otherwise, if the macro is invoked without an argument, then search for
-a C++ compiler under the likely names (first @code{g++} and @code{c++}
-then other names).  If none of those checks succeed, then as a last
-resort set @code{CXX} to @code{gcc}.
-
-This macro may, however, be invoked with an optional first argument
-which, if specified, must be a space separated list of C++ compilers to
-search for.  This just gives the user an opportunity to specify an
-alternative search list for the C++ compiler.  For example, if you
-didn't like the default order, then you could invoke @code{AC_PROG_CXX}
-like this:
-
address@hidden
-AC_PROG_CXX(cl KCC CC cxx cc++ xlC aCC c++ g++ egcs gcc)
address@hidden example
-
-If using the @sc{gnu} C++ compiler, set shell variable @code{GXX} to
address@hidden  If output variable @code{CXXFLAGS} was not already set, set
-it to @option{-g -O2} for the @sc{gnu} C++ compiler (@option{-O2} on
-systems where G++ does not accept @option{-g}), or @option{-g} for other
-compilers.
address@hidden defmac
-
address@hidden AC_PROG_CXXCPP
address@hidden PROG_CXXCPP
address@hidden CXXCPP
-Set output variable @code{CXXCPP} to a command that runs the C++
-preprocessor.  If @samp{$CXX -E} doesn't work, @file{/lib/cpp} is used.
-It is only portable to run @code{CXXCPP} on files with a @file{.c},
address@hidden, or @file{.cc} extension.
-
-If the current language is C++ (@pxref{Language Choice}), many of the
-specific test macros use the value of @code{CXXCPP} indirectly by
-calling @code{AC_TRY_CPP}, @code{AC_CHECK_HEADER},
address@hidden, or @code{AC_EGREP_CPP}.
-
-Some preprocessors don't indicate missing include files by the error
-status.  For such preprocessors an internal variable is set that causes
-other macros to check the standard error from the preprocessor and
-consider the test failed if any warnings have been reported.  However,
-it is not known whether such broken preprocessors exist for C++.
address@hidden defmac
-
address@hidden AC_PROG_F77 (@ovar{compiler-search-list})
address@hidden PROG_FORTRAN
address@hidden F77
address@hidden FFLAGS
-Determine a Fortran 77 compiler to use.  If @code{F77} is not already
-set in the environment, then check for @code{g77} and @code{f77}, and
-then some other names.  Set the output variable @code{F77} to the name
-of the compiler found.
-
-This macro may, however, be invoked with an optional first argument
-which, if specified, must be a space separated list of Fortran 77
-compilers to search for.  This just gives the user an opportunity to
-specify an alternative search list for the Fortran 77 compiler.  For
-example, if you didn't like the default order, then you could invoke
address@hidden like this:
-
address@hidden
-AC_PROG_F77(fl32 f77 fort77 xlf cf77 g77 f90 xlf90)
address@hidden example
-
-If using @code{g77} (the @sc{gnu} Fortran 77 compiler), then
address@hidden will set the shell variable @code{G77} to @samp{yes}.
-If the output variable @code{FFLAGS} was not already set in the
-environment, then set it to @option{-g -02} for @code{g77} (or @option{-O2}
-where @code{g77} does not accept @option{-g}).  Otherwise, set
address@hidden to @option{-g} for all other Fortran 77 compilers.
address@hidden defmac
-
address@hidden AC_PROG_F77_C_O
address@hidden PROG_F77_C_O
address@hidden F77_NO_MINUS_C_MINUS_O
-Test if the Fortran 77 compiler accepts the options @option{-c} and
address@hidden simultaneously, and define @code{F77_NO_MINUS_C_MINUS_O} if it
-does not.
address@hidden defmac
-
address@hidden AC_PROG_GCC_TRADITIONAL
address@hidden PROG_GCC_TRADITIONAL
address@hidden CC
-Add @option{-traditional} to output variable @code{CC} if using the
address@hidden C compiler and @code{ioctl} does not work properly without
address@hidden  That usually happens when the fixed header files
-have not been installed on an old system.  Since recent versions of the
address@hidden C compiler fix the header files automatically when installed,
-this is becoming a less prevalent problem.
address@hidden defmac
-
-
address@hidden C Compiler, Fortran 77 Compiler, Compilers and Preprocessors, 
Existing Tests
address@hidden C Compiler Characteristics

 The following macros check for C compiler or machine architecture
 features.  To check for characteristics not listed here, use
@@ -4643,33 +4580,114 @@ @node C Compiler, Fortran 77 Compiler, C
 @end example
 @end defmac

address@hidden FIXME: What the heck is this macro doing here?  Move it out of
address@hidden the way, in its proper section!!!
address@hidden AC_CHECK_SIZEOF (@var{type}, @ovar{unused}, @ovar{includes})
address@hidden CHECK_SIZEOF
-Define @address@hidden (@pxref{Standard Symbols}) to be the
-size in bytes of @var{type}.  If @samp{type} is unknown, it gets a size
-of 0.  If no @var{includes} are specified, the default includes are used
-(@pxref{Default Includes}).  If you provide @var{include}, make sure to
-include @file{stdio.h} which is required for this macro to run.
address@hidden AC_PROG_GCC_TRADITIONAL
address@hidden PROG_GCC_TRADITIONAL
address@hidden CC
+Add @option{-traditional} to output variable @code{CC} if using the
address@hidden C compiler and @code{ioctl} does not work properly without
address@hidden  That usually happens when the fixed header files
+have not been installed on an old system.  Since recent versions of the
address@hidden C compiler fix the header files automatically when installed,
+this is becoming a less prevalent problem.
address@hidden defmac

-This macro now works even when cross-compiling.  The @var{unused}
-argument was used when cross-compiling.

-For example, the call
address@hidden C++ Compiler, Fortran 77 Compiler, C Compiler, Compilers and 
Preprocessors
address@hidden C++ Compiler Characteristics
+
+
address@hidden AC_PROG_CXX (@ovar{compiler-search-list})
address@hidden PROG_CXX
address@hidden CXX
address@hidden CXXFLAGS
+Determine a C++ compiler to use.  Check if the environment variable
address@hidden or @code{CCC} (in that order) is set; if so, then set output
+variable @code{CXX} to its value.
+
+Otherwise, if the macro is invoked without an argument, then search for
+a C++ compiler under the likely names (first @code{g++} and @code{c++}
+then other names).  If none of those checks succeed, then as a last
+resort set @code{CXX} to @code{gcc}.
+
+This macro may, however, be invoked with an optional first argument
+which, if specified, must be a space separated list of C++ compilers to
+search for.  This just gives the user an opportunity to specify an
+alternative search list for the C++ compiler.  For example, if you
+didn't like the default order, then you could invoke @code{AC_PROG_CXX}
+like this:

 @example
-AC_CHECK_SIZEOF(int *)
+AC_PROG_CXX(cl KCC CC cxx cc++ xlC aCC c++ g++ egcs gcc)
 @end example

address@hidden
-defines @code{SIZEOF_INT_P} to be 8 on DEC Alpha AXP systems.
+If using the @sc{gnu} C++ compiler, set shell variable @code{GXX} to
address@hidden  If output variable @code{CXXFLAGS} was not already set, set
+it to @option{-g -O2} for the @sc{gnu} C++ compiler (@option{-O2} on
+systems where G++ does not accept @option{-g}), or @option{-g} for other
+compilers.
address@hidden defmac
+
address@hidden AC_PROG_CXXCPP
address@hidden PROG_CXXCPP
address@hidden CXXCPP
+Set output variable @code{CXXCPP} to a command that runs the C++
+preprocessor.  If @samp{$CXX -E} doesn't work, @file{/lib/cpp} is used.
+It is only portable to run @code{CXXCPP} on files with a @file{.c},
address@hidden, or @file{.cc} extension.
+
+If the current language is C++ (@pxref{Language Choice}), many of the
+specific test macros use the value of @code{CXXCPP} indirectly by
+calling @code{AC_TRY_CPP}, @code{AC_CHECK_HEADER},
address@hidden, or @code{AC_EGREP_CPP}.
+
+Some preprocessors don't indicate missing include files by the error
+status.  For such preprocessors an internal variable is set that causes
+other macros to check the standard error from the preprocessor and
+consider the test failed if any warnings have been reported.  However,
+it is not known whether such broken preprocessors exist for C++.
 @end defmac



address@hidden Fortran 77 Compiler, System Services, C Compiler, Existing Tests
address@hidden Fortran 77 Compiler Characteristics
address@hidden Fortran 77 Compiler,  , C++ Compiler, Compilers and Preprocessors
address@hidden Fortran 77 Compiler Characteristics
+
address@hidden AC_PROG_F77 (@ovar{compiler-search-list})
address@hidden PROG_FORTRAN
address@hidden F77
address@hidden FFLAGS
+Determine a Fortran 77 compiler to use.  If @code{F77} is not already
+set in the environment, then check for @code{g77} and @code{f77}, and
+then some other names.  Set the output variable @code{F77} to the name
+of the compiler found.
+
+This macro may, however, be invoked with an optional first argument
+which, if specified, must be a space separated list of Fortran 77
+compilers to search for.  This just gives the user an opportunity to
+specify an alternative search list for the Fortran 77 compiler.  For
+example, if you didn't like the default order, then you could invoke
address@hidden like this:
+
address@hidden
+AC_PROG_F77(fl32 f77 fort77 xlf cf77 g77 f90 xlf90)
address@hidden example
+
+If using @code{g77} (the @sc{gnu} Fortran 77 compiler), then
address@hidden will set the shell variable @code{G77} to @samp{yes}.
+If the output variable @code{FFLAGS} was not already set in the
+environment, then set it to @option{-g -02} for @code{g77} (or @option{-O2}
+where @code{g77} does not accept @option{-g}).  Otherwise, set
address@hidden to @option{-g} for all other Fortran 77 compilers.
address@hidden defmac
+
address@hidden AC_PROG_F77_C_O
address@hidden PROG_F77_C_O
address@hidden F77_NO_MINUS_C_MINUS_O
+Test if the Fortran 77 compiler accepts the options @option{-c} and
address@hidden simultaneously, and define @code{F77_NO_MINUS_C_MINUS_O} if it
+does not.
address@hidden defmac
+

 The following macros check for Fortran 77 compiler characteristics.  To
 check for characteristics not listed here, use @code{AC_TRY_COMPILE}
@@ -4779,7 +4797,7 @@ @node Fortran 77 Compiler, System Servic
 language other than C/C++.
 @end defmac

address@hidden System Services, UNIX Variants, Fortran 77 Compiler, Existing 
Tests
address@hidden System Services, UNIX Variants, Compilers and Preprocessors, 
Existing Tests
 @section System Services

 The following macros check for operating system services or capabilities.