flex: worked a bit on modernizing flex build

base/flex/flex.conf

@@ -2,7 +2,7 @@
 # This copyright note is auto-generated by ./scripts/Create-CopyPatch.
 #
 # Filename: package/.../flex/flex.conf
-# Copyright (C) 2016 The OpenSDE Project
+# Copyright (C) 2016 - 2020 The OpenSDE Project
 # Copyright (C) 2004 - 2006 The T2 SDE Project
 # Copyright (C) 1998 - 2004 Clifford Wolf
 #
@@ -20,8 +20,18 @@ pkg_flex_postmake() {
 
 }
 
+if ! atstage native; then
+	var_append configcache ' ' 'ac_cv_func_malloc_0_nonnull=yes'
+	var_append configcache ' ' 'ac_cv_func_realloc_0_nonnull=yes'
+fi
+
 hook_add postmake 5 "pkg_flex_postmake"
 hook_add preconf 5 "sed -i -e '/test-bison-yylloc/d' -e '/test-bison-yylval/d' tests/Makefile.in"
 # don't mix with host system
 var_append GCC_WRAPPER_REMOVE ' ' "-I/usr/include"
 
+var_append confopt ' ' "--enable-shared"
+var_append confopt ' ' "--disable-static"
+
+# Delete the following line when updating flex!
+hook_add preconf 5 "aclocal ; autoconf ; automake --add-missing"

base/flex/flex.desc

@@ -2,7 +2,7 @@
 [COPY] This copyright note is auto-generated by ./scripts/Create-CopyPatch.
 [COPY]
 [COPY] Filename: package/.../flex/flex.desc
-[COPY] Copyright (C) 2006 - 2017 The OpenSDE Project
+[COPY] Copyright (C) 2006 - 2020 The OpenSDE Project
 [COPY] Copyright (C) 2004 - 2006 The T2 SDE Project
 [COPY] Copyright (C) 1998 - 2004 Clifford Wolf
 [COPY]
@@ -33,5 +33,5 @@
 [V] 2.6.3
 [P] X 01-3-5---9 102.080
 
-[D] 1929379314 flex-2.6.3.tar.gz !https://github.com/westes/flex/releases/download/v2.6.3/flex-2.6.3.tar.gz
+[D] 1929379314 flex-2.6.3.tar.gz !https://github.com/westes/flex/releases/download/v2.6.4/flex-2.6.3.tar.gz