Create proc to test for alias attribute support from targets.

Use this test to disable ecos tests for alias support if the target does not
support them.

From-SVN: r30415

gcc/testsuite/ChangeLog

 1999-11-05  Nick Clifton  <nickc@cygnus.com>
 
+	* lib/target-supports.exp: New file: Provide procs to test for 
+	features supported by the target.
+	(check_weak_available): Moved here from ecos.exp.
+	(check_alias_available): New proc: Determine of the target
+	toolchain supports the alias attribute.
+	
+	* gcc.dg/special/ecos.exp: Move check_weak_available to
+	target-supports.exp. 
+	(alias-1.c): Only perform the test if the target supports
+	aliases. 
+	(wkali-1.c): Only perform the test if the target supports
+	aliases. 
+
 	* gcc.dg/990506-0.c: Expect error messages from cross
 	targets as well as native targets.
 

gcc/testsuite/gcc.dg/special/ecos.exp

@@ -32,32 +32,7 @@ load_lib gcc-dg.exp
 ###############################
 # proc check_weak_available { }
 ###############################
-
-# weak symbols are only supported in some configs/object formats
-# this proc returns 1 if they're support, 0 if they're not, or -1 if unsure
-
-proc check_weak_available { } {
-    global target_cpu
-
-    # All mips targets should support it
-    
-    if { [ string first "mips" $target_cpu ] >= 0 } {
-        return 1
-    }
-
-    # ELF and ECOFF support it. a.out does with gas/gld but may also with
-    # other linkers, so we should try it
-
-    set objformat [gcc_target_object_format]
-
-    switch $objformat {
-        elf      { return 1 }
-        ecoff    { return 1 }
-        a.out    { return 1 }
-        unknown  { return -1 }
-        default  { return 0 }
-    }
-}
+# has been moved to:  gcc/testsuite/lib/target-supports.exp
 
 ##########
 # weak-1.c
@@ -111,7 +86,11 @@ if { [ check_weak_available ] == 1 } {
 ###########
 
 dg-init
-dg-runtest "$srcdir/$subdir/alias-1.c" "" ""
+switch [check_alias_available "$srcdir/$subdir/alias-1.c"] {
+    yes     { dg-runtest "$srcdir/$subdir/alias-1.c" "" "" }
+    no      { unsupported "alias-1.c" }
+    default { fail "alias-1.c" }
+}
 dg-finish
 
 ###########
@@ -119,7 +98,11 @@ dg-finish
 ###########
 
 dg-init
-dg-runtest "$srcdir/$subdir/wkali-1.c" "" ""
+switch [check_alias_available "$srcdir/$subdir/wkali-1.c"] {
+    yes     { dg-runtest "$srcdir/$subdir/wkali-1.c" "" "" }
+    no      { unsupported "wkali-1.c" }
+    default { fail "wkali-1.c" }
+}
 dg-finish
 
 ###########

gcc/testsuite/lib/target-supports.exp

+#   Copyright (C) 1999 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+# 
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  
+
+# Please email any bugs, comments, and/or additions to this file to:
+# gcc-patches@gcc.gnu.org
+
+# This file defines procs for determining features supported by the target.
+
+###############################
+# proc check_weak_available { }
+###############################
+
+# weak symbols are only supported in some configs/object formats
+# this proc returns 1 if they're supported, 0 if they're not, or -1 if unsure
+
+proc check_weak_available { } {
+    global target_cpu
+
+    # All mips targets should support it
+    
+    if { [ string first "mips" $target_cpu ] >= 0 } {
+        return 1
+    }
+
+    # ELF and ECOFF support it. a.out does with gas/gld but may also with
+    # other linkers, so we should try it
+
+    set objformat [gcc_target_object_format]
+
+    switch $objformat {
+        elf      { return 1 }
+        ecoff    { return 1 }
+        a.out    { return 1 }
+        unknown  { return -1 }
+        default  { return 0 }
+    }
+}
+
+###############################
+# proc check_alias_available { }
+###############################
+
+# Determine if the target toolchain supports the alias attribute.
+# Parameter is the pathname of a file that can be used to test the alias support.
+# Returns yes if it does.
+# Returns no if it does not.
+# Returns dontknow if something went wrong
+# For an example of the use of this function, see gcc.dg/special/ecos.exp
+
+proc check_alias_available { testfile } {
+    global alias_available_saved
+    
+    if [info exists alias_available_saved] {
+        verbose "check_alias_available  returning saved $alias_available_saved" 2
+    } else {
+        verbose "check_alias_available  compiling testfile $testfile" 2
+	set lines [gcc_target_compile $testfile "tmp.o" object ""]
+	
+	if [string match "" $lines] then {
+	    # No error messages, everything is OK.
+	    set alias_available_saved yes
+	} else {
+	    if [regexp "alias definitions not supported" $lines] {
+		verbose "check_alias_available  target does not support aliases" 2
+
+		set objformat [gcc_target_object_format]
+
+		if { $objformat == "elf" } {
+		    verbose "check_alias_available  but target uses ELF format, so it ought to" 2
+		    set alias_available_saved dontknow
+		} else {
+		    set alias_available_saved no
+		}
+	    } else {
+		set alias_available_saved dontknow
+	    }
+	}
+	
+	verbose "check_alias_available  returning $alias_available_saved" 2
+    }
+
+    return $alias_available_saved
+}