refactor: Make field_NxM.h headers self-contained

Author: hebasto

.github/workflows/ci.yml

@@ -748,7 +748,7 @@ jobs:
 
       - name: Test script
         run: |
-          ./tools/check_header.sh src/field.h
+          ./tools/check_header.sh src/field.h src/field_5x52.h src/field_10x26.h
 
   sage:
     name: "SageMath prover"

src/field.h

@@ -29,13 +29,6 @@
  * implementation also provides a secp256k1_fe_verify routine to verify that
  * these fields match the run-time value and perform internal consistency
  * checks. */
-#ifdef VERIFY
-#  define SECP256K1_FE_VERIFY_FIELDS \
-    int magnitude; \
-    int normalized;
-#else
-#  define SECP256K1_FE_VERIFY_FIELDS
-#endif
 
 #if defined(SECP256K1_WIDEMUL_INT128)
 #include "field_5x52.h"

src/field_10x26.h

@@ -30,7 +30,10 @@ typedef struct {
      *     sum(i=0..9, n[i] << (i*26)) < p
      *     (together these imply n[9] <= 2^22 - 1)
      */
-    SECP256K1_FE_VERIFY_FIELDS
+#ifdef VERIFY
+    int magnitude;
+    int normalized;
+#endif
 } secp256k1_fe;
 
 /* Unpacks a constant into a overlapping multi-limbed FE element. */

src/field_5x52.h

@@ -30,7 +30,10 @@ typedef struct {
      *     sum(i=0..4, n[i] << (i*52)) < p
      *     (together these imply n[4] <= 2^48 - 1)
      */
-    SECP256K1_FE_VERIFY_FIELDS
+#ifdef VERIFY
+    int magnitude;
+    int normalized;
+#endif
 } secp256k1_fe;
 
 /* Unpacks a constant into a overlapping multi-limbed FE element. */