add clang

05/tcc-final/lib/bt-log.c

@@ -0,0 +1,37 @@
+/* ------------------------------------------------------------- */
+/* function to get a stack backtrace on demand with a message */
+
+#include <stdarg.h>
+#include <stdio.h>
+#include <string.h>
+
+int (*__rt_error)(void*, void*, const char *, va_list);
+
+#ifdef _WIN32
+# define DLL_EXPORT __declspec(dllexport)
+#else
+# define DLL_EXPORT
+#endif
+
+DLL_EXPORT int tcc_backtrace(const char *fmt, ...)
+{
+    va_list ap;
+    int ret;
+
+    if (__rt_error) {
+        void *fp = __builtin_frame_address(1);
+        void *ip = __builtin_return_address(0);
+        va_start(ap, fmt);
+        ret = __rt_error(fp, ip, fmt, ap);
+        va_end(ap);
+    } else {
+        const char *p;
+        if (fmt[0] == '^' && (p = strchr(fmt + 1, fmt[0])))
+            fmt = p + 1;
+        va_start(ap, fmt);
+        ret = vfprintf(stderr, fmt, ap);
+        va_end(ap);
+        fprintf(stderr, "\n"), fflush(stderr);
+    }
+    return ret;
+}