Fix [121786c0]: image svg upstream out of bound read nanosvg#262

Author: jan.nijtmans

changes.md

@@ -17,6 +17,8 @@ to the userbase.
 
 # Bug fixes
  - [inaccurate scrollbar error-message](https://core.tcl-lang.org/tk/tktview/f88118)
+ - [Build tk 9.0.1 failed on macos 10.13](https://core.tcl-lang.org/tk/tktview/cb5d77)
+ - [image svg upstream out of bound read nanosvg#262](https://core.tcl-lang.org/tk/tktview/121786)
 
 Release Tk 9.0.1 arises from the check-in with tag `core-9-0-1`.
 

generic/nanosvg.h

@@ -1341,7 +1341,7 @@ static unsigned int nsvg__parseColorRGB(const char* str)
 				while (*str && nsvg__isdigit(*str)) str++;	/* skip fractional part */
 			}
 			if (*str == '%') str++; else break;
-			while (nsvg__isspace(*str)) str++;
+			while (*str && nsvg__isspace(*str)) str++;
 			if (*str == delimiter[i]) str++;
 			else break;
 		}