[bug#75807] [PATCH,WIP] Support for the Algol 68 language

[Jose E. Marchesi]

Hello.

This patch adds support for the Algol 68 programming language to
Automake.  It is based on the Algol 68 GCC front-end, which is currently
under development [1]. A WIP series got sent to gcc-patches in January
[2], and the front-end is temporarily hosted in the sourceware forge
until integration in GCC is completed [3].

The full language is (almost) already implemented, the compiler is
useful and I plan to send official patches for inclusion in GCC 16 very
soon.

In the meanwhile, I would like to have both autoconf and automake
support ready to be added upstream once the front-end lands.

This WIP seems to work for me: make, make install, make dist, etc.  With
a Makefile.am like this:

----
bin_PROGRAMS = program
godcc_SOURCES = program.a68
----

But I am not familiar with the Automake internals and it is likely I am
missing something and/or doing something wrong.  Comments are welcome.

A patch adding Algol 68 support to autoconf has been sent to
autoconf-patches@.

Salud!

[1] https://gcc.gnu.org/wiki/Algol68FrontEnd
[2] 
https://inbox.sourceware.org/gcc-patches/20250101020952.18404-1-jose.marchesi@oracle.com/T/#t
 
[3] https://forge.sourceforge.org/jemarch/a68-gcc


    Add support for the Algol 68 programming language.
    
    * NEWS: Add entry for Algol 68.
    * bin/automake.in: Call register_language for Algol 68.
      (resolve_linker): handle A68LINK.
      (%_am_macro_for_cond): Add entry for am__fastdepGA68.
    * configure.ac: Look for ga68 and set GNU_GA68 and GNU_A68FLAGS if fuond.
    * lib/Automake/Variable.pm (%_ac_macro_for_var): Add entries for GA68
      and GA68FLAGS.

diff --git a/NEWS b/NEWS
index b4c50ffc6..9da978c39 100644
--- a/NEWS
+++ b/NEWS
@@ -4,6 +4,10 @@ please see NEWS-future and start following the advice there 
now.
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 New in 1.x:
 
+* New supported languages:
+
+  - Support for Algol 68 has been added; based on the GNU Algol 68 compiler.
+
 * Miscellaneous changes
 
    - Only require the presence of an ABOUT-NLS file at the 'gnits'
diff --git a/bin/automake.in b/bin/automake.in
index 5d3e7c766..bc5c3838a 100644
--- a/bin/automake.in
+++ b/bin/automake.in
@@ -1023,6 +1023,24 @@ register_language ('name' => 'java',
                   'pure' => 1,
                   'extensions' => ['.java', '.class', '.zip', '.jar']);
 
+# Algol 68 in GCC
+register_language ('name' => 'a68',
+                   'Name' => 'Algol 68',
+                   'config_vars' => ['GA68'],
+                   'linker' => 'A68LINK',
+                   'link' => '$(A68LD) $(AM_A68FLAGS) $(A68FLAGS) 
$(AM_LDFLAGS) $(LDFLAGS) -o $@',
+                  'flags' => ['A68FLAGS'],
+                  'compile' => '$(GA68) $(AM_A68FLAGS) $(A68FLAGS)',
+                  'ccer' => 'GA68',
+                  'compiler' => 'A68COMPILE',
+                  'compile_flag' => '-c',
+                  'output_flag' => '-o',
+                  'libtool_tag' => 'GA68',
+                  'lder' => 'A68LD',
+                  'ld' => '$(GA68)',
+                  'pure' => 1,
+                  'extensions' => ['.a68']);
+
 ################################################################
 
 # Error reporting functions.
@@ -5564,7 +5582,7 @@ EOF
          if (0 == keys %libtool_tags)
            {
              # Hardcode the tags supported by Libtool 1.5.
-             %libtool_tags = (CC => 1, CXX => 1, GCJ => 1, F77 => 1);
+             %libtool_tags = (CC => 1, CXX => 1, GCJ => 1, F77 => 1, GA68 => 
1);
            }
        }
     }
@@ -6057,7 +6075,7 @@ sub resolve_linker
 {
     my (%linkers) = @_;
 
-    foreach my $l (qw(GCJLINK OBJCXXLINK CXXLINK F77LINK FCLINK OBJCLINK 
UPCLINK))
+    foreach my $l (qw(GCJLINK A68LINK OBJCXXLINK CXXLINK F77LINK FCLINK 
OBJCLINK UPCLINK))
     {
        return $l if defined $linkers{$l};
     }
@@ -6176,11 +6194,12 @@ my %_am_macro_for_cond =
   (
   AMDEP => "one of the compiler tests\n"
           . "    AC_PROG_CC, AC_PROG_CXX, AC_PROG_OBJC, AC_PROG_OBJCXX,\n"
-          . "    AM_PROG_AS, AM_PROG_GCJ, AM_PROG_UPC",
+          . "    AM_PROG_AS, AM_PROG_GCJ, AM_PROG_UPC, AM_PROG_A68",
   am__fastdepCC => 'AC_PROG_CC',
   am__fastdepCCAS => 'AM_PROG_AS',
   am__fastdepCXX => 'AC_PROG_CXX',
   am__fastdepGCJ => 'AM_PROG_GCJ',
+  am__fastdepGA68 => 'AM_PROG_GA68',
   am__fastdepOBJC => 'AC_PROG_OBJC',
   am__fastdepOBJCXX => 'AC_PROG_OBJCXX',
   am__fastdepUPC => 'AM_PROG_UPC'
diff --git a/configure.ac b/configure.ac
index 0a9e1904e..295bd2749 100644
--- a/configure.ac
+++ b/configure.ac
@@ -565,6 +565,16 @@ if test "$GNU_F77" != false; then
         _AM_SKIP_COMP_TESTS([GNU Fortran 77])])
 fi
 
+# GNU Algol 68 compiler.
+AC_ARG_VAR([GNU_GA68],    [GNU Algol 68 compiler])
+AC_ARG_VAR([GNU_A68FLAGS], [GNU Algol 68 compiler flags])
+AC_CHECK_TOOLS([GNU_GA68], [ga68], [false])
+if test "$GNU_GA68" != false; then
+   AS_IF([AM_RUN_LOG([$GNU_GA68 --version && $GNU_GA68 -v])], [],
+   [AC_MSG_WARN([botched installation for GNU Algol 68 compiler])
+   _AM_SKIP_COMP_TESTS([GNU Algol 68])])
+fi
+
 # GNU Java compiler.
 AC_ARG_VAR([GNU_GCJ], [GNU Java compiler])
 AC_ARG_VAR([GNU_GCJFLAGS], [GNU Java compiler flags])
diff --git a/lib/Automake/Variable.pm b/lib/Automake/Variable.pm
index 6e90b81f2..ccf065803 100644
--- a/lib/Automake/Variable.pm
+++ b/lib/Automake/Variable.pm
@@ -183,6 +183,8 @@ my %_ac_macro_for_var =
    CXX => 'AC_PROG_CXX',
    CXXFLAGS => 'AC_PROG_CXX',
    F77 => 'AC_PROG_F77',
+   GA68 => 'AC_PROG_GA68',
+   A68FLAGS => 'AC_PROG_GA68',
    FFLAGS => 'AC_PROG_F77',
    FC => 'AC_PROG_FC',
    FCFLAGS => 'AC_PROG_FC',