diff --git a/binding/miniffi-binding.cpp b/binding/miniffi-binding.cpp
index aba42828..3bb33115 100644
--- a/binding/miniffi-binding.cpp
+++ b/binding/miniffi-binding.cpp
@@ -312,7 +312,7 @@ RB_METHOD(MiniFFI_call) {
                "test esp, ebx\n"
                "movnz esp, ebx"
                : "+a"(ret)
-               : "c"(nimport * 4), "b"(&sp), "S"(&param), "D"(ApiFunction)
+               : "c"(nimport * 4), "S"(&param), "D"(ApiFunction)
                : "memory");
 #endif
 
diff --git a/meson.build b/meson.build
index a93ec481..4d1784de 100644
--- a/meson.build
+++ b/meson.build
@@ -8,7 +8,7 @@ host_system = host_machine.system()
 
 compilers = {'cpp': meson.get_compiler('cpp'), 'objc': meson.get_compiler('objc'), 'objcpp': meson.get_compiler('objcpp')}
 
-if compilers['objc'].get_id() != 'clang' or compilers['objcpp'].get_id() != 'clang'
+if compilers['objc'].get_id() != 'clang' or compilers['objcpp'].get_id() != 'clang' or compilers['cpp'].get_id() != 'clang'
     error('This program must be built with Clang! ( export CC=clang OBJC=clang CXX=clang++ OBJCXX=clang++ )')
 endif