Move __check_failed out of line so anyone can implement it

kernel/src/arch/Serial.cpp

@@ -1,4 +1,5 @@
 #include "arch/Serial.h"
+#include "arch/CPU.h"
 #include <Format.h>
 
 namespace Serial
@@ -33,4 +34,16 @@ namespace Serial
         va_end(ap);
         return rc;
     }
+}
+
+static bool g_check_already_failed = false;
+
+_noreturn bool __check_failed(const char* file, const char* line, const char* func, const char* expr)
+{
+    if (!g_check_already_failed)
+    { // Avoid endlessly failing when trying to report a failed check.
+        g_check_already_failed = true;
+        Serial::printf("ERROR: Check failed at %s:%s, in %s: %s\n", file, line, func, expr);
+    }
+    CPU::efficient_halt();
 }

luna/CMakeLists.txt

@@ -6,6 +6,7 @@ set(FREESTANDING_SOURCES
 
 set(SOURCES
     ${FREESTANDING_SOURCES}
+    Check.cpp
 )
 
 add_library(luna-freestanding ${FREESTANDING_SOURCES})

luna/Check.cpp

@@ -0,0 +1,6 @@
+#include <Attributes.h>
+
+_weak _noreturn bool __check_failed(const char*, const char*, const char*, const char*)
+{
+    __builtin_trap();
+}

luna/Check.h

@@ -1,22 +1,9 @@
 #pragma once
-#ifdef IN_MOON
+#include <Attributes.h>
-#include "arch/Serial.h"
 
-[[noreturn]] inline bool __check_failed(const char* string)
+extern _noreturn bool __check_failed(const char* file, const char* line, const char* func, const char* expr);
-{
-    Serial::print("CHECK FAILED: ");
-    Serial::println(string);
-    for (;;)
-        ;
-}
-#else
-[[noreturn]] inline bool __check_failed(const char*)
-{
-    __builtin_trap();
-}
-#endif
 
 #define STRINGIZE(x) #x
 #define STRINGIZE_VALUE_OF(x) STRINGIZE(x)
 
-#define check(expr) (expr) || __check_failed("at " __FILE__ ":" STRINGIZE_VALUE_OF(__LINE__) ": " #expr)
+#define check(expr) (expr) || __check_failed(__FILE__, STRINGIZE_VALUE_OF(__LINE__), __PRETTY_FUNCTION__, #expr)