Fix #50: revert to -O2 optimization

The while loop in xstrlcpy() breaks when -O3 is used.

Makefile

@@ -3,7 +3,7 @@ VERSION = 1.5
 PREFIX ?= /usr/local
 MANPREFIX = $(PREFIX)/share/man
 
-CFLAGS += -O3 -Wall -Wextra -Wno-unused-parameter
+CFLAGS += -O2 -Wall -Wextra -Wno-unused-parameter
 LDLIBS = -lreadline
 
 ifeq ($(shell pkg-config ncursesw && echo 1),1)

scripts/test/mktest.sh

@@ -37,3 +37,4 @@ touch 'unicode/Malgudi Days - मालगुडी डेज - E05. Swami and F
 chmod +x 'unicode/Malgudi Days - मालगुडी डेज - E05. Swami and Friends - स्वामी और उसके दोस्त (Part 2)'
 touch 'unicode/Führer'
 touch 'unicode/Eso eso aamar ghare eso ♫ এসো এসো আমার ঘরে এসো ♫ Swagatalakshmi Dasgupta'
+touch 'max_chars_filename_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx'