Fix "maybe uninitialized" warning.

ChangeLog

@@ -232,6 +232,9 @@ not doing so for [\d-X] (and similar escapes), as is documented.
 
 54. Fixed a MIPS issue in the JIT compiler reported by Joshua Kinard.
 
+55. Fixed a "maybe uninitialized" warning for class_uchardata in \p handling in 
+pcre2_compile() which could never actually trigger (code should have been cut
+out when Unicode support is disabled).
 
 
 Version 10.23 14-February-2017

maint/ManyConfigTests

@@ -124,6 +124,7 @@ if [ $? -eq 0 ] && grep GCC /tmp/pcre2ccversion >/dev/null; then
   CFLAGS="$CFLAGS -Wnested-externs"
   CFLAGS="$CFLAGS -pedantic"
   CFLAGS="$CFLAGS -Wuninitialized"
+  CFLAGS="$CFLAGS -Wmaybe-uninitialized" 
   CFLAGS="$CFLAGS -Wmissing-prototypes"
   CFLAGS="$CFLAGS -Wstrict-prototypes"
 fi

src/pcre2_compile.c

@@ -5356,6 +5356,10 @@ for (;; pptr++)
             options & ~PCRE2_CASELESS, cb, PRIV(vspace_list));
           break;
 
+          /* If Unicode is not supported, \P and \p are not allowed and are
+          faulted at parse time, so will never appear here. */
+
+#ifdef SUPPORT_UNICODE
           case ESC_p:
           case ESC_P:
             {
@@ -5364,12 +5368,11 @@ for (;; pptr++)
             *class_uchardata++ = (escape == ESC_p)? XCL_PROP : XCL_NOTPROP;
             *class_uchardata++ = ptype;
             *class_uchardata++ = pdata;
-#ifdef SUPPORT_WIDE_CHARS
             xclass_has_prop = TRUE;
-#endif
             class_has_8bitchar--;                /* Undo! */
             }
           break;
+#endif
           }
 
         goto CONTINUE_CLASS;