diff --git a/codon/runtime/lib.h b/codon/runtime/lib.h
index 886d8243..a63d01c5 100644
--- a/codon/runtime/lib.h
+++ b/codon/runtime/lib.h
@@ -56,6 +56,8 @@ SEQ_FUNC void seq_assert_failed(seq_str_t file, seq_int_t line);
 
 SEQ_FUNC void *seq_alloc(size_t n);
 SEQ_FUNC void *seq_alloc_atomic(size_t n);
+SEQ_FUNC void *seq_alloc_uncollectable(size_t n);
+SEQ_FUNC void *seq_alloc_atomic_uncollectable(size_t n);
 SEQ_FUNC void *seq_calloc(size_t m, size_t n);
 SEQ_FUNC void *seq_calloc_atomic(size_t m, size_t n);
 SEQ_FUNC void *seq_realloc(void *p, size_t newsize, size_t oldsize);
diff --git a/codon/runtime/re.cpp b/codon/runtime/re.cpp
index fc808612..bfb6204f 100644
--- a/codon/runtime/re.cpp
+++ b/codon/runtime/re.cpp
@@ -75,7 +75,7 @@ template <typename KV> struct GCMapAllocator : public std::allocator<KV> {
 
   template <typename KV1> GCMapAllocator(const GCMapAllocator<KV1> &) noexcept {}
 
-  KV *allocate(std::size_t n) { return (KV *)seq_alloc(n * sizeof(KV)); }
+  KV *allocate(std::size_t n) { return (KV *)seq_alloc_uncollectable(n * sizeof(KV)); }
 
   void deallocate(KV *p, std::size_t n) { seq_free(p); }