diff --git a/config/watcom.h b/config/watcom.h
index b43b7fb4..029a36f8 100644
--- a/config/watcom.h
+++ b/config/watcom.h
@@ -69,5 +69,6 @@
 #define HAVE_UNISTD_H 1
 #define HAVE_VSNPRINTF 1
 #define STDC_HEADERS 1
+#define inline __inline
 
 #endif /* NASM_CONFIG_WATCOM_H */
diff --git a/include/compiler.h b/include/compiler.h
index 061b3441..4cecf9ce 100644
--- a/include/compiler.h
+++ b/include/compiler.h
@@ -81,6 +81,7 @@
 #include <stddef.h>
 #include <stdarg.h>
 #include <stdio.h>
+#include <limits.h>
 
 #ifdef HAVE_SYS_TYPES_H
 # include <sys/types.h>
@@ -248,4 +249,20 @@ char *strsep(char **, const char *);
 # define pure_func
 #endif
 
+/* Watcom doesn't handle switch statements with 64-bit types, hack around it */
+#ifdef __WATCOM__
+# define BOGUS_CASE 0x76543210
+
+static inline unsigned int watcom_switch_hack(uint64_t x)
+{
+    if (x > UINT_MAX)
+        return BOGUS_CASE;
+    else
+        return (unsigned int)x;
+}
+
+# define switch(x) switch(watcom_switch_hack(x))
+# define default case BOGUS_CASE: default
+#endif
+
 #endif	/* NASM_COMPILER_H */