package/botan: needs C++20

C++20 is mandatory since bump to version 3.2.0 in commit
2f8feb66204ff661e9fd5f508e2dfd1ebc0f2813 and
https://github.com/randombit/botan/commit/e2efb744ceda875b193bc5ce589f2c45ceaa3a82
resulting in the following build failure:

powerpc-linux-g++.br_real: error: unrecognized command line option '-std=c++20'; did you mean '-std=c++2a'?

BR2_TOOLCHAIN_HAS_GCC_BUG_64735 dependency can be dropped as gcc > 7 is
not affected by this bug

Fixes: 2f8feb66204ff661e9fd5f508e2dfd1ebc0f2813
 - http://autobuild.buildroot.org/results/4171515ce33832fb07c8b42cda2575067f9e9859

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/botan/Config.in

@@ -14,10 +14,9 @@ config BR2_PACKAGE_BOTAN_ARCH_SUPPORTS
 config BR2_PACKAGE_BOTAN
 	bool "botan"
 	depends on BR2_INSTALL_LIBSTDCPP
-	depends on BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
+	depends on BR2_TOOLCHAIN_GCC_AT_LEAST_10 # C++20
 	depends on BR2_TOOLCHAIN_HAS_THREADS
 	depends on BR2_PACKAGE_BOTAN_ARCH_SUPPORTS
-	depends on !BR2_TOOLCHAIN_HAS_GCC_BUG_64735 # std::future
 	select BR2_PACKAGE_BOOST_FILESYSTEM if BR2_PACKAGE_BOOST && BR2_TOOLCHAIN_SUPPORTS_ALWAYS_LOCKFREE_ATOMIC_INTS
 	select BR2_PACKAGE_BOOST_SYSTEM if BR2_PACKAGE_BOOST && BR2_TOOLCHAIN_SUPPORTS_ALWAYS_LOCKFREE_ATOMIC_INTS
 	help
@@ -25,11 +24,7 @@ config BR2_PACKAGE_BOTAN
 
 	  http://botan.randombit.net
 
-comment "botan needs a toolchain w/ C++, threads, gcc >= 4.8"
+comment "botan needs a toolchain w/ C++, threads, gcc >= 10"
 	depends on !BR2_TOOLCHAIN_HAS_THREADS || !BR2_INSTALL_LIBSTDCPP \
-		|| !BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
+		|| !BR2_TOOLCHAIN_GCC_AT_LEAST_10
 	depends on BR2_PACKAGE_BOTAN_ARCH_SUPPORTS
-
-comment "botan needs a toolchain not affected by GCC bug 64735"
-	depends on BR2_PACKAGE_BOTAN_ARCH_SUPPORTS
-	depends on BR2_TOOLCHAIN_HAS_GCC_BUG_64735

package/strongswan/Config.in

@@ -35,19 +35,14 @@ config BR2_PACKAGE_STRONGSWAN_BOTAN
 	bool "botan"
 	depends on BR2_PACKAGE_BOTAN_ARCH_SUPPORTS
 	depends on BR2_INSTALL_LIBSTDCPP
-	depends on BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
-	depends on !BR2_TOOLCHAIN_HAS_GCC_BUG_64735
+	depends on BR2_TOOLCHAIN_GCC_AT_LEAST_10 # botan
 	select BR2_PACKAGE_BOTAN
 
-comment "botan backend needs a toolchain w/ C++, gcc >= 4.8"
+comment "botan backend needs a toolchain w/ C++, gcc >= 10"
 	depends on !BR2_INSTALL_LIBSTDCPP \
-		|| !BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
+		|| !BR2_TOOLCHAIN_GCC_AT_LEAST_10
 	depends on BR2_PACKAGE_BOTAN_ARCH_SUPPORTS
 
-comment "botan backend needs a toolchain not affected by GCC bug 64735"
-	depends on BR2_PACKAGE_BOTAN_ARCH_SUPPORTS
-	depends on BR2_TOOLCHAIN_HAS_GCC_BUG_64735
-
 config BR2_PACKAGE_STRONGSWAN_OPENSSL
 	bool "OpenSSL"
 	select BR2_PACKAGE_OPENSSL