Added patch fixing build with tcl8.6

tix-8.4.3-tcl86.patch

@@ -0,0 +1,24 @@
+diff --git a/generic/tixGrSort.c b/generic/tixGrSort.c
+index 7dee30f..d45f51d 100644
+--- a/generic/tixGrSort.c
++++ b/generic/tixGrSort.c
+@@ -425,7 +425,7 @@ SortCompareProc(first, second)
+ 	}
+     } else {
+ 	int oldLength;
+-	char *end;
++	char *end, *result;
+ 
+ 	/*
+ 	 * Generate and evaluate a command to determine which string comes
+@@ -447,8 +447,8 @@ SortCompareProc(first, second)
+ 	 * Parse the result of the command.
+ 	 */
+ 
+-	order = strtol(sortInterp->result, &end, 0);
+-	if ((end == sortInterp->result) || (*end != 0)) {
++	order = strtol(result = Tcl_GetStringResult(sortInterp), &end, 0);
++	if ((end == result) || (*end != 0)) {
+ 	    Tcl_ResetResult(sortInterp);
+ 	    Tcl_AppendResult(sortInterp,
+ 		    "comparison command returned non-numeric result",

tix.spec

@@ -15,7 +15,8 @@ URL: http://tix.sourceforge.net/
 Source0: http://downloads.sourceforge.net/project/%{name}/%{name}/%{version}/Tix%{version}-src.tar.gz
 #  0: Fixes BZ#81297 (soname of libraries)
 Patch0: tix-8.4.2-link.patch
-Requires: tcl(abi) = 8.5
+Patch1: tix-8.4.3-tcl86.patch
+Requires: tcl(abi) = %{tcl_version}
 Requires: tcl >= %{tcltkver}, tk >= %{tcltkver}
 Requires: /etc/ld.so.conf.d
 Buildrequires: tcl-devel >= %{tcltkver}, tk-devel >= %{tcltkver}
@@ -57,6 +58,7 @@ This package contains the tix documentation
 %prep
 %setup -q -n Tix%{version}
 %patch0 -p1 -b .link
+%patch1 -p1 -b .tcl86
 
 # Remove executable permission of images in html documentation
 chmod ugo-x docs/html/gif/tix/*.png docs/html/gif/tix/*.gif \