libphobos: Add --with-libphobos-druntime-only option.

The intended purpose of the option is both for targets that don't
support phobos yet, and for gdc itself to support bootstrapping itself
as a self-hosted D compiler.

The libphobos testsuite has been updated to only add libphobos to the
search paths if it's being built.  A new D2 testsuite directive
RUNNABLE_PHOBOS_TEST has also been patched in to disable some runnable
tests that have phobos dependencies, of which is a temporary measure
until upstream DMD fixes or removes these tests entirely.

gcc/testsuite/ChangeLog:

	* lib/gdc-utils.exp (gdc-convert-test): Add dg-skip-if for tests that
	depending on the phobos standard library.

libphobos/ChangeLog:

	* configure: Regenerate.
	* configure.ac: Add --with-libphobos-druntime-only option and the
	conditional ENABLE_LIBDRUNTIME_ONLY.
	* configure.tgt: Define LIBDRUNTIME_ONLY.
	* src/Makefile.am: Add phobos sources if not ENABLE_LIBDRUNTIME_ONLY.
	* src/Makefile.in: Regenerate.
	* testsuite/testsuite_flags.in: Add phobos path if compiling phobos.

gcc/testsuite/gdc.test/runnable/builtin.d

@@ -116,3 +116,4 @@ int main()
     printf("Success\n");
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/complex.d

@@ -460,3 +460,4 @@ int main(char[][] args)
     return 0;
 }
 
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/constfold.d

@@ -672,3 +672,4 @@ int main()
     printf("Success\n");
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/foreach4.d

@@ -928,3 +928,4 @@ int main()
     printf("Success\n");
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/ifti.d

@@ -118,3 +118,4 @@ void main() {
     }
 
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/implicit.d

@@ -479,3 +479,4 @@ void main()
 
     writefln("Success");
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/inner.d

@@ -916,3 +916,4 @@ int main()
     printf("Success\n");
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/interpret.d

@@ -3609,3 +3609,4 @@ int main()
     printf("Success\n");
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/issue8671.d

@@ -3,3 +3,4 @@ void main()
 {
     double t = 1.0 - uniform(0.0, 1.0);
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/lazy.d

@@ -308,3 +308,4 @@ int main()
     printf("Success\n");
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/mars1.d

@@ -1723,3 +1723,4 @@ int main()
     printf("Success\n");
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/mixin1.d

@@ -1468,3 +1468,4 @@ int main()
     printf("Success\n");
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/mixin2.d

@@ -361,3 +361,4 @@ void main()
 
     writeln("Success");
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/s2ir.d

@@ -95,3 +95,4 @@ int main()
     writefln("Success\n");
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/stress.d

@@ -725,3 +725,4 @@ void CLASS()
         }
     }
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/template4.d

@@ -1164,3 +1164,4 @@ int main()
     printf("Success\n");
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/template9.d

@@ -4965,3 +4965,4 @@ int main()
     printf("Success\n");
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/test10942.d

@@ -24,3 +24,4 @@ mixin(getEnum(1087));
 
 void main() { }
 
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/test11.d

@@ -1390,3 +1390,4 @@ int main(string[] argv)
 }
 
 
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/test12.d

@@ -1250,3 +1250,4 @@ int main(string[] argv)
     return 0;
 }
 
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/test12197.d

@@ -10,3 +10,4 @@ void main()
     foo(a);
     assert(a[0] == 10000);
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/test15.d

@@ -1439,3 +1439,4 @@ int main()
     printf("Success\n");
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/test22.d

@@ -1306,3 +1306,4 @@ int main()
     printf("Success\n");
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/test23.d

@@ -1566,3 +1566,4 @@ void main()
 
     printf("Success\n");
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/test24.d

@@ -8,3 +8,4 @@ void main()
 {
     string hi = std.string.format("%s", 3);
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/test27.d

@@ -11,3 +11,4 @@ int main()
     return 0;
 }
 
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/test28.d

@@ -1318,3 +1318,4 @@ void main()
     printf("Success\n");
 }
 
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/test34.d

@@ -1292,3 +1292,4 @@ void main()
 }
 
 
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/test37.d

@@ -11,3 +11,4 @@ void main()
     // imports in a subdirectory of the -J path
     writefln(import("std14198/uni.d"));
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/test42.d

@@ -6438,3 +6438,4 @@ int main()
     return 0;
 }
 
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/test5305.d

@@ -5,3 +5,4 @@ void map(real function(real) f) { }
 int main() { map(&sqrt); return 0; }
 
 
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/test60.d

@@ -20,3 +20,4 @@ void main()
 
     writeln("Success");
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/testaa.d

@@ -1383,3 +1383,4 @@ int main()
     printf("Success\n");
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/testbitarray.d

@@ -14,3 +14,4 @@ void main() {
 }
 
 
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/testdstress.d

@@ -930,3 +930,4 @@ int main()
     printf("Success\n");
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/testfile.d

@@ -22,3 +22,4 @@ int main()
     printf("Success\n");
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/testformat.d

@@ -123,3 +123,4 @@ int main()
     std.stdio.writefln("Success");
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/testline.d

@@ -41,3 +41,4 @@ void checkFileSpec(Object o){
 writeln(str);
         assert(str[start .. start+3]=="(1)");
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/testmmfile.d

@@ -117,3 +117,4 @@ int main()
 
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/testscope2.d

@@ -246,3 +246,4 @@ void main()
     printf("Success\n");
 }
 
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/testsignals.d

@@ -111,3 +111,4 @@ int main()
     printf("Success\n");
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/testsocket.d

@@ -48,3 +48,4 @@ int main ()
 }
 
 
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/teststdio.d

@@ -31,3 +31,4 @@ void main()
     } while (!feof(fp));
     //fclose(fp);
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/testthread2.d

@@ -106,3 +106,4 @@ void main() {
     }
 }
 
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/testtypeid.d

@@ -684,3 +684,4 @@ int main()
 
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/traits.d

@@ -1606,3 +1606,4 @@ int main()
     writeln("Success");
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/wc.d

@@ -48,3 +48,4 @@ int main (string[] args)
     }
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/wc2.d

@@ -72,3 +72,4 @@ int main (string[] args)
     }
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/wc3.d

@@ -70,3 +70,4 @@ int main (string[] args)
     }
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/xtest46.d

@@ -8283,3 +8283,4 @@ int main()
     printf("Success\n");
     return 0;
 }
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/gdc.test/runnable/xtest55.d

@@ -22,3 +22,4 @@ int main()
     return 0;
 }
 
+// RUNNABLE_PHOBOS_TEST

gcc/testsuite/lib/gdc-utils.exp

@@ -208,6 +208,7 @@ proc gdc-convert-test { base test } {
 
     set extra_sources ""
     set extra_files ""
+    set needs_phobos 0
 
     upvar 1 compilable_do_what compilable_do_what
     set compilable_output_file_ext ""
@@ -296,6 +297,11 @@ proc gdc-convert-test { base test } {
 	    }
 	    regsub -- {COMPILED_IMPORTS.*$} $copy_line "" out_line
 
+	} elseif [regexp -- {RUNNABLE_PHOBOS_TEST} $copy_line match sources] {
+	    # RUNNABLE_PHOBOS_TEST annotates tests that import the std module.
+	    # It will need skipping if phobos is not available on the target.
+	    regsub -- {RUNNABLE_PHOBOS_TEST.*$} $copy_line "" out_line
+	    set needs_phobos 1
 	}
 
 	puts $fdout $out_line
@@ -331,6 +337,9 @@ proc gdc-convert-test { base test } {
 	    if ![isnative] {
 		puts $fdout "// { dg-final { output-exists } }"
 	    }
+	    if $needs_phobos {
+		puts $fdout "// { dg-skip-if \"imports phobos\" { ! d_runtime_has_std_library } }"
+	    }
 	}
 
 	compilable {

libphobos/configure

@@ -638,6 +638,8 @@ GDCFLAGSX
 libtool_VERSION
 SPEC_PHOBOS_DEPS
 CHECKING_DFLAGS
+ENABLE_LIBDRUNTIME_ONLY_FALSE
+ENABLE_LIBDRUNTIME_ONLY_TRUE
 ENABLE_LIBPHOBOS_FALSE
 ENABLE_LIBPHOBOS_TRUE
 gdc_include_dir
@@ -840,6 +842,7 @@ with_cross_host
 enable_version_specific_runtime_libs
 with_toolexeclibdir
 enable_libphobos
+with_libdruntime_only
 enable_libphobos_checking
 '
       ac_precious_vars='build_alias
@@ -1509,6 +1512,8 @@ Optional Packages:
   --with-toolexeclibdir=DIR
                           install libraries built with a cross compiler within
                           DIR
+  --with-libphobos-druntime-only={yes,no,auto}
+                          build only the druntime library (default: auto)
 
 Some influential environment variables:
   CC          C compiler command
@@ -11645,7 +11650,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11648 "configure"
+#line 11653 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11751,7 +11756,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11754 "configure"
+#line 11759 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -15230,8 +15235,27 @@ fi
 { $as_echo "$as_me:${as_lineno-$LINENO}: result: $enable_libphobos" >&5
 $as_echo "$enable_libphobos" >&6; }
 
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for --with-libphobos-druntime-only" >&5
+$as_echo_n "checking for --with-libphobos-druntime-only... " >&6; }
+
+# Check whether --with-libdruntime-only was given.
+if test "${with_libdruntime_only+set}" = set; then :
+  withval=$with_libdruntime_only;
+else
+  with_libdruntime_only=auto
+fi
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $with_libdruntime_only" >&5
+$as_echo "$with_libdruntime_only" >&6; }
+
+case "$with_libdruntime_only" in
+  yes|no|auto) ;;
+  *) as_fn_error $? "Invalid argument for --with-libphobos-druntime-only" "$LINENO" 5 ;;
+esac
+
 # See if supported.
 unset LIBPHOBOS_SUPPORTED
+unset LIBDRUNTIME_ONLY
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for host support for libphobos" >&5
 $as_echo_n "checking for host support for libphobos... " >&6; }
 . ${srcdir}/configure.tgt
@@ -15274,6 +15298,22 @@ else
 fi
 
 
+# Decide if only libdruntime should be built.
+case $LIBDRUNTIME_ONLY:$with_libdruntime_only in
+*:no)  only_libdruntime=no  ;;
+*:yes) only_libdruntime=yes ;;
+yes:*) only_libdruntime=yes ;;
+*:*)   only_libdruntime=no  ;;
+esac
+ if test x$only_libdruntime = xyes; then
+  ENABLE_LIBDRUNTIME_ONLY_TRUE=
+  ENABLE_LIBDRUNTIME_ONLY_FALSE='#'
+else
+  ENABLE_LIBDRUNTIME_ONLY_TRUE='#'
+  ENABLE_LIBDRUNTIME_ONLY_FALSE=
+fi
+
+
 # Enable expensive internal checks
 # Check whether --enable-libphobos-checking was given.
 if test "${enable_libphobos_checking+set}" = set; then :
@@ -15577,6 +15617,10 @@ if test -z "${ENABLE_LIBPHOBOS_TRUE}" && test -z "${ENABLE_LIBPHOBOS_FALSE}"; th
   as_fn_error $? "conditional \"ENABLE_LIBPHOBOS\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5
 fi
+if test -z "${ENABLE_LIBDRUNTIME_ONLY_TRUE}" && test -z "${ENABLE_LIBDRUNTIME_ONLY_FALSE}"; then
+  as_fn_error $? "conditional \"ENABLE_LIBDRUNTIME_ONLY\" was never defined.
+Usually this means the macro was only invoked conditionally." "$LINENO" 5
+fi
 
 : "${CONFIG_STATUS=./config.status}"
 ac_write_fail=0

libphobos/configure.ac

@@ -152,8 +152,21 @@ AC_ARG_ENABLE(libphobos,
   [AS_HELP_STRING([--enable-libphobos], [Enable libphobos])])
 AC_MSG_RESULT($enable_libphobos)
 
+AC_MSG_CHECKING([for --with-libphobos-druntime-only])
+AC_ARG_WITH(libdruntime-only,
+  AS_HELP_STRING([--with-libphobos-druntime-only={yes,no,auto}],
+		 [build only the druntime library (default: auto)]),,
+	    [with_libdruntime_only=auto])
+AC_MSG_RESULT($with_libdruntime_only)
+
+case "$with_libdruntime_only" in
+  yes|no|auto) ;;
+  *) AC_MSG_ERROR([Invalid argument for --with-libphobos-druntime-only]) ;;
+esac
+
 # See if supported.
 unset LIBPHOBOS_SUPPORTED
+unset LIBDRUNTIME_ONLY
 AC_MSG_CHECKING([for host support for libphobos])
 . ${srcdir}/configure.tgt
 case ${host} in
@@ -187,6 +200,15 @@ yes:*) use_libphobos=yes ;;
 esac
 AM_CONDITIONAL(ENABLE_LIBPHOBOS, test x$use_libphobos = xyes)
 
+# Decide if only libdruntime should be built.
+case $LIBDRUNTIME_ONLY:$with_libdruntime_only in
+*:no)  only_libdruntime=no  ;;
+*:yes) only_libdruntime=yes ;;
+yes:*) only_libdruntime=yes ;;
+*:*)   only_libdruntime=no  ;;
+esac
+AM_CONDITIONAL(ENABLE_LIBDRUNTIME_ONLY, test x$only_libdruntime = xyes)
+
 # Enable expensive internal checks
 AC_ARG_ENABLE(libphobos-checking,
 [AS_HELP_STRING([[--enable-libphobos-checking[=LIST]]],

libphobos/configure.tgt

@@ -22,6 +22,7 @@
 # Disable the libphobos or libdruntime components on untested or known
 # broken systems.  More targets shall be added after testing.
 LIBPHOBOS_SUPPORTED=no
+LIBDRUNTIME_ONLY=auto
 case "${target}" in
   aarch64*-*-linux*)
 	LIBPHOBOS_SUPPORTED=yes

libphobos/src/Makefile.am

@@ -70,6 +70,12 @@ install-data-local:
 # https://gist.github.com/jpf91/8744acebc9dcf1e9d1a35cdff20afbb2
 # Can't use wildcards here:
 # https://www.gnu.org/software/automake/manual/html_node/Wildcards.html
+if ENABLE_LIBDRUNTIME_ONLY
+
+PHOBOS_DSOURCES =
+
+else
+
 PHOBOS_DSOURCES = etc/c/curl.d etc/c/sqlite3.d etc/c/zlib.d \
 	std/algorithm/comparison.d std/algorithm/internal.d \
 	std/algorithm/iteration.d std/algorithm/mutation.d \
@@ -132,3 +138,5 @@ PHOBOS_DSOURCES = etc/c/curl.d etc/c/sqlite3.d etc/c/zlib.d \
 	std/utf.d std/uuid.d std/variant.d std/windows/charset.d \
 	std/windows/registry.d std/windows/syserror.d std/xml.d std/zip.d \
 	std/zlib.d
+
+endif

libphobos/testsuite/testsuite_flags.in

@@ -35,8 +35,11 @@ case ${query} in
       GDCPATHS_default="-nostdinc"
       GDCPATHS_config="-B${BUILD_DIR}/src
                        -I${BUILD_DIR}/libdruntime
-                       -I${SRC_DIR}/libdruntime
-                       -I${SRC_DIR}/src"
+                       -I${SRC_DIR}/libdruntime"
+      # Include phobos in search path if compiling in library.
+      if [ "x@ENABLE_LIBDRUNTIME_ONLY_FALSE@" = "x" ]; then
+         GDCPATHS_config="${GDCPATHS_config} -I${SRC_DIR}/src"
+      fi
       echo ${GDCPATHS_default} ${GDCPATHS_config}
       ;;
     --gdcldflags)