diff --git a/include/secp256k1.h b/include/secp256k1.h
index 325f35eb0488b..75ffe40527591 100644
--- a/include/secp256k1.h
+++ b/include/secp256k1.h
@@ -122,18 +122,6 @@ typedef int (*secp256k1_nonce_function)(
 #  endif
 # endif
 
-# if (!defined(__STDC_VERSION__) || (__STDC_VERSION__ < 199901L) )
-#  if SECP256K1_GNUC_PREREQ(2,7)
-#   define SECP256K1_INLINE __inline__
-#  elif (defined(_MSC_VER))
-#   define SECP256K1_INLINE __inline
-#  else
-#   define SECP256K1_INLINE
-#  endif
-# else
-#  define SECP256K1_INLINE inline
-# endif
-
 /*  When this header is used at build-time the SECP256K1_BUILD define needs to be set
  *  to correctly setup export attributes and nullness checks.  This is normally done
  *  by secp256k1.c but to guard against this header being included before secp256k1.c
diff --git a/src/field_5x52_asm_impl.h b/src/field_5x52_asm_impl.h
index a2118044ab381..e8efa61085dc1 100644
--- a/src/field_5x52_asm_impl.h
+++ b/src/field_5x52_asm_impl.h
@@ -14,6 +14,8 @@
 #ifndef SECP256K1_FIELD_INNER5X52_IMPL_H
 #define SECP256K1_FIELD_INNER5X52_IMPL_H
 
+#include "util.h"
+
 SECP256K1_INLINE static void secp256k1_fe_mul_inner(uint64_t *r, const uint64_t *a, const uint64_t * SECP256K1_RESTRICT b) {
 /**
  * Registers: rdx:rax = multiplication accumulator
diff --git a/src/field_5x52_int128_impl.h b/src/field_5x52_int128_impl.h
index 18567b95f3933..b2a391dec93d4 100644
--- a/src/field_5x52_int128_impl.h
+++ b/src/field_5x52_int128_impl.h
@@ -10,6 +10,7 @@
 #include <stdint.h>
 
 #include "int128.h"
+#include "util.h"
 
 #ifdef VERIFY
 #define VERIFY_BITS(x, n) VERIFY_CHECK(((x) >> (n)) == 0)
diff --git a/src/group_impl.h b/src/group_impl.h
index 82ce3f8d8bb75..7ec069a80ca36 100644
--- a/src/group_impl.h
+++ b/src/group_impl.h
@@ -9,6 +9,7 @@
 
 #include "field.h"
 #include "group.h"
+#include "util.h"
 
 /* Begin of section generated by sage/gen_exhaustive_groups.sage. */
 #define SECP256K1_G_ORDER_7 SECP256K1_GE_CONST(\
diff --git a/src/int128_native_impl.h b/src/int128_native_impl.h
index 996e542cf9cc0..7f02e1590bbea 100644
--- a/src/int128_native_impl.h
+++ b/src/int128_native_impl.h
@@ -2,6 +2,7 @@
 #define SECP256K1_INT128_NATIVE_IMPL_H
 
 #include "int128.h"
+#include "util.h"
 
 static SECP256K1_INLINE void secp256k1_u128_load(secp256k1_uint128 *r, uint64_t hi, uint64_t lo) {
     *r = (((uint128_t)hi) << 64) + lo;
diff --git a/src/int128_struct_impl.h b/src/int128_struct_impl.h
index 2eb337cb5483c..3073f314b0d89 100644
--- a/src/int128_struct_impl.h
+++ b/src/int128_struct_impl.h
@@ -2,6 +2,7 @@
 #define SECP256K1_INT128_STRUCT_IMPL_H
 
 #include "int128.h"
+#include "util.h"
 
 #if defined(_MSC_VER) && (defined(_M_X64) || defined(_M_ARM64)) /* MSVC */
 #    include <intrin.h>
diff --git a/src/modules/extrakeys/main_impl.h b/src/modules/extrakeys/main_impl.h
index e1003052f4c62..73520044576ae 100644
--- a/src/modules/extrakeys/main_impl.h
+++ b/src/modules/extrakeys/main_impl.h
@@ -9,6 +9,7 @@
 
 #include "../../../include/secp256k1.h"
 #include "../../../include/secp256k1_extrakeys.h"
+#include "../../util.h"
 
 static SECP256K1_INLINE int secp256k1_xonly_pubkey_load(const secp256k1_context* ctx, secp256k1_ge *ge, const secp256k1_xonly_pubkey *pubkey) {
     return secp256k1_pubkey_load(ctx, ge, (const secp256k1_pubkey *) pubkey);
diff --git a/src/scalar_4x64_impl.h b/src/scalar_4x64_impl.h
index 1b83575b3eb9f..0809698b12700 100644
--- a/src/scalar_4x64_impl.h
+++ b/src/scalar_4x64_impl.h
@@ -10,6 +10,7 @@
 #include "checkmem.h"
 #include "int128.h"
 #include "modinv64_impl.h"
+#include "util.h"
 
 /* Limbs of the secp256k1 order. */
 #define SECP256K1_N_0 ((uint64_t)0xBFD25E8CD0364141ULL)
diff --git a/src/scalar_8x32_impl.h b/src/scalar_8x32_impl.h
index c433adce75bc0..92f428796d184 100644
--- a/src/scalar_8x32_impl.h
+++ b/src/scalar_8x32_impl.h
@@ -9,6 +9,7 @@
 
 #include "checkmem.h"
 #include "modinv32_impl.h"
+#include "util.h"
 
 /* Limbs of the secp256k1 order. */
 #define SECP256K1_N_0 ((uint32_t)0xD0364141UL)
diff --git a/src/scalar_low_impl.h b/src/scalar_low_impl.h
index e7800833395cd..5ce1c2d2ac8d9 100644
--- a/src/scalar_low_impl.h
+++ b/src/scalar_low_impl.h
@@ -9,6 +9,7 @@
 
 #include "checkmem.h"
 #include "scalar.h"
+#include "util.h"
 
 #include <string.h>
 
diff --git a/src/testrand.h b/src/testrand.h
index d109bb9f8b036..721099d039259 100644
--- a/src/testrand.h
+++ b/src/testrand.h
@@ -7,6 +7,8 @@
 #ifndef SECP256K1_TESTRAND_H
 #define SECP256K1_TESTRAND_H
 
+#include "util.h"
+
 /* A non-cryptographic RNG used only for test infrastructure. */
 
 /** Seed the pseudorandom number generator for testing. */
diff --git a/src/testrand_impl.h b/src/testrand_impl.h
index e9b9d7ded44bc..1b7481a53b8ac 100644
--- a/src/testrand_impl.h
+++ b/src/testrand_impl.h
@@ -13,6 +13,7 @@
 
 #include "testrand.h"
 #include "hash.h"
+#include "util.h"
 
 static uint64_t secp256k1_test_state[4];
 static uint64_t secp256k1_test_rng_integer;
diff --git a/src/tests_exhaustive.c b/src/tests_exhaustive.c
index 86b9334caedb2..ad17d8d392e3b 100644
--- a/src/tests_exhaustive.c
+++ b/src/tests_exhaustive.c
@@ -20,6 +20,7 @@
 #include "testrand_impl.h"
 #include "ecmult_compute_table_impl.h"
 #include "ecmult_gen_compute_table_impl.h"
+#include "util.h"
 
 static int count = 2;
 
diff --git a/src/util.h b/src/util.h
index e75c5ad5523ce..f980f47bdc7f3 100644
--- a/src/util.h
+++ b/src/util.h
@@ -7,6 +7,8 @@
 #ifndef SECP256K1_UTIL_H
 #define SECP256K1_UTIL_H
 
+#include "../include/secp256k1.h"
+
 #include <stdlib.h>
 #include <stdint.h>
 #include <stdio.h>
@@ -17,6 +19,18 @@
 #define DEBUG_CONFIG_MSG(x) "DEBUG_CONFIG: " x
 #define DEBUG_CONFIG_DEF(x) DEBUG_CONFIG_MSG(#x "=" STR(x))
 
+# if (!defined(__STDC_VERSION__) || (__STDC_VERSION__ < 199901L) )
+#  if SECP256K1_GNUC_PREREQ(2,7)
+#   define SECP256K1_INLINE __inline__
+#  elif (defined(_MSC_VER))
+#   define SECP256K1_INLINE __inline
+#  else
+#   define SECP256K1_INLINE
+#  endif
+# else
+#  define SECP256K1_INLINE inline
+# endif
+
 typedef struct {
     void (*fn)(const char *text, void* data);
     const void* data;