Configuration: rework how dependency making is handled

Previously, we had dependency making pretty much hard coded in the
build file templates, with a bit of an exception for Unix family
platforms, where we had different cases depending on what dependency
making program was found.

With the Embarcadero C++ builder, a separate scheme appeared, with a
different logic.

This change merges the two, and introduces two config target
attributes:

    makedepcmd          The program to use, where this is relevant.
                        This replaces the earlier configuration
                        attribute 'makedepprog'.
    makedep_scheme      This is a keyword that can be used by build
                        files templates to produce different sorts of
                        commands, but most importantly, to pass as
                        argument to util/add-depend.pl, which uses
                        this keyword as a "producer" for the
                        dependency lines.

If the config target doesn't define the 'makedep_scheme' attribute,
Configure tries to figure it out by looking for GCC compatible
compilers or for the 'makedepend' command.

Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
(Merged from https://github.com/openssl/openssl/pull/15006)

1 files changed, 6 insertions, 8 deletions

diff --git a/Configurations/unix-Makefile.tmpl b/Configurations/unix-Makefile.tmpl
index be6036c227..e2df304061 100644
--- a/Configurations/unix-Makefile.tmpl
+++ b/Configurations/unix-Makefile.tmpl
@@ -3,7 +3,8 @@
 ##
 ## {- join("\n## ", @autowarntext) -}
 {-
-     our $makedepprog = platform->makedepprog();
+     our $makedep_scheme = $config{makedep_scheme};
+     our $makedepcmd = platform->makedepcmd();
 
      sub windowsdll { $config{target} =~ /^(?:Cygwin|mingw)/ }
 
@@ -315,7 +316,7 @@ CXXFLAGS={- join(' ', @{$config{CXXFLAGS}}) -}
 LDFLAGS= {- join(' ', @{$config{LDFLAGS}}) -}
 EX_LIBS= {- join(' ', @{$config{LDLIBS}}) -}
 
-MAKEDEPEND={- $config{makedepprog} -}
+MAKEDEPEND={- $config{makedepcmd} -}
 
 PERL={- $config{PERL} -}
 
@@ -570,9 +571,7 @@ distclean: clean
 # concatenate only if that is true.
 depend:
 	@: {- output_off() if $disabled{makedepend}; "" -}
-	@$(PERL) $(SRCDIR)/util/add-depends.pl {-
-		 defined $makedepprog  && $makedepprog =~ /\/makedepend/
-                 ? 'makedepend' : 'gcc' -}
+	@$(PERL) $(SRCDIR)/util/add-depends.pl "{- $makedep_scheme -}"
 	@: {- output_on() if $disabled{makedepend}; "" -}
 
 # Install helper targets #############################################
@@ -1516,8 +1515,7 @@ EOF
 $obj: $deps
 	$cmd $incs $defs $cmdflags -c -o \$\@ $srcs
 EOF
-      } elsif (defined $makedepprog && $makedepprog !~ /\/makedepend/
-               && !grep /\.rc$/, @srcs) {
+      } elsif ($makedep_scheme eq 'gcc' && !grep /\.rc$/, @srcs) {
           $recipe .= <<"EOF";
 $obj: $deps
 	$cmd $incs $defs $cmdflags -MMD -MF $dep.tmp -MT \$\@ -c -o \$\@ $srcs
@@ -1533,7 +1531,7 @@ EOF
 $obj: $deps
 	$cmd $incs $defs $cmdflags $cmdcompile -o \$\@ $srcs
 EOF
-          if (defined $makedepprog  && $makedepprog =~ /\/makedepend/) {
+          if ($makedep_scheme eq 'makedepend') {
               $recipe .= <<"EOF";
 	\$(MAKEDEPEND) -f- -Y -- $incs $cmdflags -- $srcs 2>/dev/null \\
 	    > $dep