diff --git a/src/parser3.h b/src/parser3.h
index d28b2a2..a20674c 100644
--- a/src/parser3.h
+++ b/src/parser3.h
@@ -17,20 +17,29 @@
 
 namespace parser3 {
 
-// Calling a continuation with buf == bufEnd means end of input
-typedef PRESERVE_NONE WeaselJsonStatus (*Continuation)(struct Parser3 *,
-                                                       char *buf, char *bufEnd);
+// The internal result of a parse step: a WeaselJsonStatus value, or kBounce.
+// It's a plain int (not WeaselJsonStatus) so the no-musttail trampoline's
+// out-of-range sentinel never forms an out-of-range enum value (that would be
+// UB, since the public WeaselJsonStatus has no fixed underlying type). parse()
+// converts back to WeaselJsonStatus at the boundary, where it is always 0..3.
+using ContinuationStatus = int;
+[[maybe_unused]] inline constexpr ContinuationStatus kBounce = -1;
 
-inline PRESERVE_NONE WeaselJsonStatus n_object2(Parser3 *self, char *buf,
-                                                char *bufEnd);
-inline PRESERVE_NONE WeaselJsonStatus n_array2(Parser3 *self, char *buf,
-                                               char *bufEnd);
-inline PRESERVE_NONE WeaselJsonStatus n_string2(Parser3 *self, char *buf,
-                                                char *bufEnd);
-inline PRESERVE_NONE WeaselJsonStatus n_string(Parser3 *self, char *buf,
-                                               char *bufEnd);
-inline PRESERVE_NONE WeaselJsonStatus n_number(Parser3 *self, char *buf,
-                                               char *bufEnd);
+// Calling a continuation with buf == bufEnd means end of input
+typedef PRESERVE_NONE ContinuationStatus (*Continuation)(struct Parser3 *,
+                                                         char *buf,
+                                                         char *bufEnd);
+
+inline PRESERVE_NONE ContinuationStatus n_object2(Parser3 *self, char *buf,
+                                                  char *bufEnd);
+inline PRESERVE_NONE ContinuationStatus n_array2(Parser3 *self, char *buf,
+                                                 char *bufEnd);
+inline PRESERVE_NONE ContinuationStatus n_string2(Parser3 *self, char *buf,
+                                                  char *bufEnd);
+inline PRESERVE_NONE ContinuationStatus n_string(Parser3 *self, char *buf,
+                                                 char *bufEnd);
+inline PRESERVE_NONE ContinuationStatus n_number(Parser3 *self, char *buf,
+                                                 char *bufEnd);
 
 // These appear in the stack of the pushdown
 // automata
@@ -121,8 +130,8 @@ struct Parser3 {
     return *(stackPtr - 1);
   }
 
-  static PRESERVE_NONE WeaselJsonStatus keepGoing(Parser3 *self, char *buf,
-                                                  char *bufEnd);
+  static PRESERVE_NONE ContinuationStatus keepGoing(Parser3 *self, char *buf,
+                                                    char *bufEnd);
 
   Symbol *stack() const { return (Symbol *)(this + 1); }
 
@@ -152,7 +161,8 @@ struct Parser3 {
 #endif
 };
 
-inline PRESERVE_NONE WeaselJsonStatus skipWhitespace(char *&buf, char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus skipWhitespace(char *&buf,
+                                                       char *bufEnd) {
   constexpr int kStride = 4;
   for (;;) {
     if (bufEnd - buf < kStride) [[unlikely]] {
@@ -171,8 +181,8 @@ inline PRESERVE_NONE WeaselJsonStatus skipWhitespace(char *&buf, char *bufEnd) {
   }
 }
 
-inline PRESERVE_NONE WeaselJsonStatus n_whitespace(Parser3 *self, char *buf,
-                                                   char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus n_whitespace(Parser3 *self, char *buf,
+                                                     char *bufEnd) {
   if (buf == bufEnd) {
     self->pop();
     MUSTTAIL return Parser3::keepGoing(self, buf, bufEnd);
@@ -184,8 +194,8 @@ inline PRESERVE_NONE WeaselJsonStatus n_whitespace(Parser3 *self, char *buf,
   MUSTTAIL return Parser3::keepGoing(self, buf, bufEnd);
 }
 
-inline PRESERVE_NONE WeaselJsonStatus n_number(Parser3 *self, char *buf,
-                                               char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus n_number(Parser3 *self, char *buf,
+                                                 char *bufEnd) {
   if (buf != bufEnd) {
     buf = (char *)self->numDfa.scan(buf, bufEnd);
     if (buf == bufEnd) {
@@ -204,9 +214,9 @@ inline PRESERVE_NONE WeaselJsonStatus n_number(Parser3 *self, char *buf,
 // Advance buf until double quote, backslash, invalid utf8, or codepoint <
 // 0x20
 template <class V>
-inline PRESERVE_NONE WeaselJsonStatus scan_string_impl(Parser3 *self,
-                                                       char *&buf,
-                                                       char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus scan_string_impl(Parser3 *self,
+                                                         char *&buf,
+                                                         char *bufEnd) {
   const auto before = buf;
 
   // Advance buf past characters that transition the accept state to itself
@@ -253,34 +263,34 @@ inline PRESERVE_NONE WeaselJsonStatus scan_string_impl(Parser3 *self,
 
 #ifdef __x86_64__
 constexpr int kLanes = 32;
-template WeaselJsonStatus
+template ContinuationStatus
 scan_string_impl<simd<int8_t, kLanes, sse::Simd_x86_SSE>>(Parser3 *, char *&,
                                                           char *);
 
-template __attribute__((target("avx2"))) WeaselJsonStatus
+template __attribute__((target("avx2"))) ContinuationStatus
 scan_string_impl<simd<int8_t, kLanes, sse::Simd_x86_AVX2>>(Parser3 *, char *&,
                                                            char *);
 
-__attribute__((target("default"))) inline PRESERVE_NONE WeaselJsonStatus
+__attribute__((target("default"))) inline PRESERVE_NONE ContinuationStatus
 scan_string(Parser3 *self, char *&buf, char *bufEnd) {
   MUSTTAIL return scan_string_impl<simd<int8_t, kLanes, sse::Simd_x86_SSE>>(
       self, buf, bufEnd);
 }
 
-__attribute__((target("avx2"))) inline PRESERVE_NONE WeaselJsonStatus
+__attribute__((target("avx2"))) inline PRESERVE_NONE ContinuationStatus
 scan_string(Parser3 *self, char *&buf, char *bufEnd) {
   MUSTTAIL return scan_string_impl<simd<int8_t, kLanes, sse::Simd_x86_AVX2>>(
       self, buf, bufEnd);
 }
 #else
-inline PRESERVE_NONE WeaselJsonStatus scan_string(Parser3 *self, char *&buf,
-                                                  char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus scan_string(Parser3 *self, char *&buf,
+                                                    char *bufEnd) {
   MUSTTAIL return scan_string_impl<simd<int8_t, 32>>(self, buf, bufEnd);
 }
 #endif
 
-inline PRESERVE_NONE WeaselJsonStatus n_value(Parser3 *self, char *buf,
-                                              char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus n_value(Parser3 *self, char *buf,
+                                                char *bufEnd) {
   if (buf == bufEnd) [[unlikely]] {
     return WeaselJson_REJECT;
   }
@@ -392,8 +402,8 @@ inline PRESERVE_NONE WeaselJsonStatus n_value(Parser3 *self, char *buf,
   MUSTTAIL return Parser3::keepGoing(self, buf, bufEnd);
 }
 
-inline PRESERVE_NONE WeaselJsonStatus n_object2(Parser3 *self, char *buf,
-                                                char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus n_object2(Parser3 *self, char *buf,
+                                                  char *bufEnd) {
   if (buf == bufEnd) [[unlikely]] {
     return WeaselJson_REJECT;
   }
@@ -428,8 +438,8 @@ inline PRESERVE_NONE WeaselJsonStatus n_object2(Parser3 *self, char *buf,
   }
 }
 
-inline PRESERVE_NONE WeaselJsonStatus n_object3(Parser3 *self, char *buf,
-                                                char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus n_object3(Parser3 *self, char *buf,
+                                                  char *bufEnd) {
   if (buf == bufEnd) [[unlikely]] {
     return WeaselJson_REJECT;
   }
@@ -474,8 +484,8 @@ inline PRESERVE_NONE WeaselJsonStatus n_object3(Parser3 *self, char *buf,
   }
 }
 
-inline PRESERVE_NONE WeaselJsonStatus n_array2(Parser3 *self, char *buf,
-                                               char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus n_array2(Parser3 *self, char *buf,
+                                                 char *bufEnd) {
   if (buf == bufEnd) [[unlikely]] {
     return WeaselJson_REJECT;
   }
@@ -500,8 +510,8 @@ inline PRESERVE_NONE WeaselJsonStatus n_array2(Parser3 *self, char *buf,
   }
 }
 
-inline PRESERVE_NONE WeaselJsonStatus n_array3(Parser3 *self, char *buf,
-                                               char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus n_array3(Parser3 *self, char *buf,
+                                                 char *bufEnd) {
   if (buf == bufEnd) [[unlikely]] {
     return WeaselJson_REJECT;
   }
@@ -532,8 +542,8 @@ inline PRESERVE_NONE WeaselJsonStatus n_array3(Parser3 *self, char *buf,
   }
 }
 
-inline PRESERVE_NONE WeaselJsonStatus n_string(Parser3 *self, char *buf,
-                                               char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus n_string(Parser3 *self, char *buf,
+                                                 char *bufEnd) {
   if (buf == bufEnd) [[unlikely]] {
     return WeaselJson_REJECT;
   }
@@ -559,8 +569,8 @@ inline int32_t read4_hex(const char *buf) {
          tables.hex[uint8_t(buf[2])] << 4 | tables.hex[uint8_t(buf[3])] << 0;
 }
 
-inline PRESERVE_NONE WeaselJsonStatus n_string2(Parser3 *self, char *buf,
-                                                char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus n_string2(Parser3 *self, char *buf,
+                                                  char *bufEnd) {
   if (buf == bufEnd) [[unlikely]] {
     return WeaselJson_REJECT;
   }
@@ -661,9 +671,8 @@ inline PRESERVE_NONE WeaselJsonStatus n_string2(Parser3 *self, char *buf,
   }
 }
 
-inline PRESERVE_NONE WeaselJsonStatus n_string_following_escape(Parser3 *self,
-                                                                char *buf,
-                                                                char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus
+n_string_following_escape(Parser3 *self, char *buf, char *bufEnd) {
   if (buf == bufEnd) [[unlikely]] {
     return WeaselJson_REJECT;
   }
@@ -701,8 +710,8 @@ inline PRESERVE_NONE WeaselJsonStatus n_string_following_escape(Parser3 *self,
   MUSTTAIL return Parser3::keepGoing(self, buf, bufEnd);
 }
 
-inline PRESERVE_NONE WeaselJsonStatus t_hex(Parser3 *self, char *buf,
-                                            char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus t_hex(Parser3 *self, char *buf,
+                                              char *bufEnd) {
   if (buf == bufEnd) [[unlikely]] {
     return WeaselJson_REJECT;
   }
@@ -721,8 +730,8 @@ inline PRESERVE_NONE WeaselJsonStatus t_hex(Parser3 *self, char *buf,
   MUSTTAIL return Parser3::keepGoing(self, buf, bufEnd);
 }
 
-inline PRESERVE_NONE WeaselJsonStatus t_hex2(Parser3 *self, char *buf,
-                                             char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus t_hex2(Parser3 *self, char *buf,
+                                               char *bufEnd) {
   if (buf == bufEnd) [[unlikely]] {
     return WeaselJson_REJECT;
   }
@@ -810,8 +819,8 @@ inline PRESERVE_NONE WeaselJsonStatus t_hex2(Parser3 *self, char *buf,
   MUSTTAIL return Parser3::keepGoing(self, buf, bufEnd);
 }
 
-inline PRESERVE_NONE WeaselJsonStatus t_hex3(Parser3 *self, char *buf,
-                                             char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus t_hex3(Parser3 *self, char *buf,
+                                               char *bufEnd) {
   if (buf == bufEnd) [[unlikely]] {
     return WeaselJson_REJECT;
   }
@@ -872,9 +881,9 @@ inline PRESERVE_NONE WeaselJsonStatus t_hex3(Parser3 *self, char *buf,
 }
 
 template <char kChar>
-inline PRESERVE_NONE WeaselJsonStatus singleCharInString(Parser3 *self,
-                                                         char *buf,
-                                                         char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus singleCharInString(Parser3 *self,
+                                                           char *buf,
+                                                           char *bufEnd) {
   if (buf == bufEnd) [[unlikely]] {
     return WeaselJson_REJECT;
   }
@@ -891,8 +900,8 @@ inline PRESERVE_NONE WeaselJsonStatus singleCharInString(Parser3 *self,
   }
 }
 
-inline PRESERVE_NONE WeaselJsonStatus n_true(Parser3 *self, char *buf,
-                                             char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus n_true(Parser3 *self, char *buf,
+                                               char *bufEnd) {
   if (buf == bufEnd) [[unlikely]] {
     return WeaselJson_REJECT;
   }
@@ -909,8 +918,8 @@ inline PRESERVE_NONE WeaselJsonStatus n_true(Parser3 *self, char *buf,
   }
 }
 
-inline PRESERVE_NONE WeaselJsonStatus n_false(Parser3 *self, char *buf,
-                                              char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus n_false(Parser3 *self, char *buf,
+                                                char *bufEnd) {
   if (buf == bufEnd) [[unlikely]] {
     return WeaselJson_REJECT;
   }
@@ -927,8 +936,8 @@ inline PRESERVE_NONE WeaselJsonStatus n_false(Parser3 *self, char *buf,
   }
 }
 
-inline PRESERVE_NONE WeaselJsonStatus n_null(Parser3 *self, char *buf,
-                                             char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus n_null(Parser3 *self, char *buf,
+                                               char *bufEnd) {
   if (buf == bufEnd) [[unlikely]] {
     return WeaselJson_REJECT;
   }
@@ -946,8 +955,8 @@ inline PRESERVE_NONE WeaselJsonStatus n_null(Parser3 *self, char *buf,
 }
 
 template <char kChar>
-inline PRESERVE_NONE WeaselJsonStatus singleChar(Parser3 *self, char *buf,
-                                                 char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus singleChar(Parser3 *self, char *buf,
+                                                   char *bufEnd) {
   if (buf == bufEnd) [[unlikely]] {
     return WeaselJson_REJECT;
   }
@@ -963,8 +972,8 @@ inline PRESERVE_NONE WeaselJsonStatus singleChar(Parser3 *self, char *buf,
   }
 }
 
-inline PRESERVE_NONE WeaselJsonStatus t_colon(Parser3 *self, char *buf,
-                                              char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus t_colon(Parser3 *self, char *buf,
+                                                char *bufEnd) {
   if (buf == bufEnd) [[unlikely]] {
     return WeaselJson_REJECT;
   }
@@ -985,8 +994,8 @@ inline PRESERVE_NONE WeaselJsonStatus t_colon(Parser3 *self, char *buf,
   }
 }
 
-inline PRESERVE_NONE WeaselJsonStatus t_eof(Parser3 *, char *buf,
-                                            char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus t_eof(Parser3 *, char *buf,
+                                              char *bufEnd) {
   if (buf != bufEnd) [[unlikely]] {
     return WeaselJson_REJECT;
   }
@@ -997,7 +1006,8 @@ constexpr inline struct ContinuationTable {
   constexpr ContinuationTable() {
     // Defaults
     for (int i = 0; i < N_SYMBOL_COUNT; ++i) {
-      continuations[i] = +[](struct Parser3 *, char *, char *) PRESERVE_NONE {
+      continuations[i] = +[](struct Parser3 *, char *, char *)
+                              PRESERVE_NONE -> ContinuationStatus {
         printf("unimplemented\n");
         return WeaselJson_REJECT;
       };
@@ -1035,26 +1045,30 @@ inline WeaselJsonStatus Parser3::parse(char *buf, int len) {
   this->dataBegin = this->writeBuf = buf;
 
 #ifdef HAS_MUSTTAIL
-  return symbolTables.continuations[top()](this, buf, buf + len);
+  // The continuation returns a value in 0..3 here (kBounce is only used by the
+  // no-musttail trampoline below), so the conversion back to the enum is in
+  // range.
+  return WeaselJsonStatus(
+      symbolTables.continuations[top()](this, buf, buf + len));
 #else
   this->stashBufForTrampoline = buf;
-  WeaselJsonStatus result;
+  ContinuationStatus result;
   while ((result = symbolTables.continuations[top()](
-              this, stashBufForTrampoline, buf + len)) == WeaselJsonStatus(-1))
+              this, stashBufForTrampoline, buf + len)) == kBounce)
     ;
-  return result;
+  return WeaselJsonStatus(result);
 #endif
 }
 
-inline PRESERVE_NONE WeaselJsonStatus Parser3::keepGoing(Parser3 *self,
-                                                         char *buf,
-                                                         char *bufEnd) {
+inline PRESERVE_NONE ContinuationStatus Parser3::keepGoing(Parser3 *self,
+                                                           char *buf,
+                                                           char *bufEnd) {
 #ifdef HAS_MUSTTAIL
   MUSTTAIL return symbolTables.continuations[self->top()](self, buf, bufEnd);
 #else
   self->stashBufForTrampoline = buf;
   (void)bufEnd;
-  return WeaselJsonStatus(-1);
+  return kBounce;
 #endif
 }