fix: build.mcpp 显式包含 <sstream>——llvm 腿抓到的

    error: implicit instantiation of undefined template
           'std::basic_istringstream<char>'

libstdc++ 通过 <fstream> 传递包含了它,libc++ 没有。这正是 validate.yml 注释里
说的「gcc 腿结构上看不见的一类 bug」。

重发 tarball(mcpp3),并在重发前用 mcpp toolchain default llvm 在本地跑过一遍
clang——免得再耗一轮 CI 才发现下一个同类问题。

Author: Sunrisepeak

pkgs/f/freedesktop.fontconfig.lua

@@ -66,10 +66,10 @@ package = {
         linux = {
             ["2.15.0"] = {
                 url = {
-                    GLOBAL = "https://github.com/mcpplibs/fontconfig/releases/download/v2.15.0/fontconfig-2.15.0-mcpp2.tar.gz",
-                    CN     = "https://gitcode.com/mcpp-res/fontconfig/releases/download/2.15.0/fontconfig-2.15.0-mcpp2.tar.gz",
+                    GLOBAL = "https://github.com/mcpplibs/fontconfig/releases/download/v2.15.0/fontconfig-2.15.0-mcpp3.tar.gz",
+                    CN     = "https://gitcode.com/mcpp-res/fontconfig/releases/download/2.15.0/fontconfig-2.15.0-mcpp3.tar.gz",
                 },
-                sha256 = "a7ac9d403f0035d2c6065237ebed8c6b0b68aab98be948ea2cc907b886be9dc2",
+                sha256 = "505938aeeafe92257ea2c08d0af0e091d25af3e8d872b0dc82478605cbf99233",
             },
         },
     },