[build] Fix some build oddness related to cross-compilation.

The Autoconf macro doesn't properly set the required variables properly
when the binaries aren't being cross-compiled. This results in the local
binaries like bin2c and ptime disregarding the compiler flags passed in
to configure scripts.

configure.ac

@@ -306,9 +306,9 @@ AS_IF([test $? -eq 0],
 
 AM_CONDITIONAL(USE_INCLUDED_YAJL, test $HAVE_LOCAL_YAJL -eq 0)
 AM_CONDITIONAL(HAVE_LIBCURL, test x"$LIBCURL" != x"")
-AM_CONDITIONAL([DISABLE_DOCUMENTATION], [ test x"$cross_compiling" != x"no" ])
+AM_CONDITIONAL([CROSS_COMPILING], [ test x"$cross_compiling" != x"no" ])
 
-USER_CXXFLAGS="${CXXFLAGS}"
+AS_VAR_SET(USER_CXXFLAGS, ["$CXXFLAGS"])
 AC_SUBST(USER_CXXFLAGS)
 
 AC_CONFIG_HEADERS([src/config.h])

src/Makefile.am

@@ -498,8 +498,13 @@ lnav_test_SOURCES = \
     test_override.c \
     $(PLUGIN_SRCS)
 
+if CROSS_COMPILING
 ptimec$(BUILD_EXEEXT): ptimec.c
 	$(AM_V_CC) $(CC_FOR_BUILD) $(CPPFLAGS_FOR_BUILD) $(LDFLAGS_FOR_BUILD) -g3 -o $@ $?
+else
+ptimec$(BUILD_EXEEXT): ptimec.c
+	$(AM_V_CC) $(CC) $(CPPFLAGS) $(LDFLAGS) -g3 -o $@ $?
+endif
 
 if HAVE_RE2C
 RE2C_FILES = data_scanner_re.cc log_level_re.cc
@@ -536,7 +541,7 @@ uncrusty:
 	(cd $(srcdir) && uncrustify -c ../lnav.cfg --replace $(SOURCES) \
 		$(HEADERS))
 
-if !DISABLE_DOCUMENTATION
+if !CROSS_COMPILING
 all-local: $(LNAV_BUILT_FILES) lnav
 	if test -w $(srcdir)/internals; then \
 		env DUMP_INTERNALS_DIR=$(srcdir)/internals DUMP_CRASH=1 ./lnav Makefile; \

tools/Makefile.am

@@ -1,8 +1,13 @@
 
 all-local: bin2c$(BUILD_EXEEXT)
 
+if CROSS_COMPILING
 bin2c$(BUILD_EXEEXT): bin2c.c
 	$(AM_V_CC) $(CC_FOR_BUILD) $(CPPFLAGS_FOR_BUILD) $(LDFLAGS_FOR_BUILD) -g3 -o $@ $? -lz
+else
+bin2c: bin2c.c
+	$(AM_V_CC) $(CC) $(CPPFLAGS) $(LDFLAGS) -g3 -o $@ $? -lz
+endif
 
 EXTRA_DIST = \
 	bin2c.c