[newlib-cygwin] Don't run UTF-8.exp test if newlib is not built with multibyte support.

[Jeff Johnston]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=58dd08ee5072c7f6246baf7d35dbf37806e78ba1

commit 58dd08ee5072c7f6246baf7d35dbf37806e78ba1
Author: Jeff Johnston <jjohnstn@redhat.com>
Date:   Mon May 2 16:03:27 2016 -0400

    Don't run UTF-8.exp test if newlib is not built with multibyte support.
    
    Submitted on behalf of Yuriy Kolerov.
    
    newlib/ChangeLog
    
    2016-04-29  Yuriy Kolerov <yuriy.kolerov@synopsys.com>
    
            testsuite/newlib.locale/UTF-8.exp: Don't run if multibyte support is
            disabled.
    
    Signed-off-by: Yuriy Kolerov <yuriy.kolerov@synopsys.com>
    Signed-off-by: Anton Kolesov <anton.kolesov@synopsys.com>

Diff:
---
 newlib/testsuite/newlib.locale/UTF-8.exp | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/newlib/testsuite/newlib.locale/UTF-8.exp b/newlib/testsuite/newlib.locale/UTF-8.exp
index e823a4f..94fcb5f 100644
--- a/newlib/testsuite/newlib.locale/UTF-8.exp
+++ b/newlib/testsuite/newlib.locale/UTF-8.exp
@@ -6,6 +6,18 @@
 
 load_lib checkoutput.exp
 
+# Don't run this test if newlib's build does not support multibyte encodings.
+set newlib_header_name "$objdir/targ-include/newlib.h"
+if [file exists $newlib_header_name] {
+    set newlib_header_fid [open $newlib_header_name r]
+    set newlib_header_text [read $newlib_header_fid]
+    close $newlib_header_fid
+    if {![regexp "#define _MB_CAPABLE" $newlib_header_text] || \
+            [regexp "#define _MB_LEN_MAX 1" $newlib_header_text]} {
+        return
+    }
+}
+
 set expected_output {
 "Set C-UTF-8 locale."
 "* U-00000000"