Local tweaks to ucpp for xrdb:

- exit on the 1st error it finds. Better than stopping processing input
- accept -P as a synonym for -l since this is what xrdb uses to suppress
  #line markers.

app/xrdb-cpp/cpp.c

@@ -115,6 +115,7 @@ void ucpp_error(long line, char *fmt, ...)
 		freemem(sc);
 	}
 	va_end(ap);
+	exit(1);
 }
 
 /*
@@ -2418,6 +2419,8 @@ static int parse_opt(int argc, char *argv[], struct lexer_state *ls)
 			ls->flags &= ~FAIL_SHARP;
 		} else if (!strcmp(argv[i], "-l")) {
 			ls->flags &= ~LINE_NUM;
+		} else if (!strcmp(argv[i], "-P")) {
+			ls->flags &= ~LINE_NUM;
 		} else if (!strcmp(argv[i], "-lg")) {
 			ls->flags |= GCC_LINE_NUM;
 		} else if (!strcmp(argv[i], "-M")) {

app/xrdb-cpp/xrdb-cpp.1

@@ -27,7 +27,7 @@ keep comments in the output.
 if a rogue '#' is encountered, do not emit an error and keep it in
 the output.
 .TP
-.BI \-l
+.B \-l, \-P
 supress the emission of '#line' directives in the output.
 .TP
 .BI \-lg