From d0cf55e13a7f0914759fe4f3afd003ff37868269 Mon Sep 17 00:00:00 2001
From: Tim Ruffing <crypto@timruffing.de>
Date: Wed, 6 Jul 2022 15:07:57 +0200
Subject: [PATCH 1/3] config: Set preprocessor defaults for ECMULT_* config
 values

This simplifies manual builds and solves one item in #929.
---
 src/ecmult.h     | 3 +++
 src/ecmult_gen.h | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/src/ecmult.h b/src/ecmult.h
index b47d8f494a803..37c73662f9c88 100644
--- a/src/ecmult.h
+++ b/src/ecmult.h
@@ -11,6 +11,9 @@
 #include "scalar.h"
 #include "scratch.h"
 
+#ifndef ECMULT_WINDOW_SIZE
+#  define ECMULT_WINDOW_SIZE 15
+#endif
 /* Noone will ever need more than a window size of 24. The code might
  * be correct for larger values of ECMULT_WINDOW_SIZE but this is not
  * tested.
diff --git a/src/ecmult_gen.h b/src/ecmult_gen.h
index f48f266461e5f..8378b8bf3fa44 100644
--- a/src/ecmult_gen.h
+++ b/src/ecmult_gen.h
@@ -10,6 +10,9 @@
 #include "scalar.h"
 #include "group.h"
 
+#ifndef ECMULT_GEN_PREC_BITS
+#  define ECMULT_GEN_PREC_BITS 4
+#endif
 #if ECMULT_GEN_PREC_BITS != 2 && ECMULT_GEN_PREC_BITS != 4 && ECMULT_GEN_PREC_BITS != 8
 #  error "Set ECMULT_GEN_PREC_BITS to 2, 4 or 8."
 #endif

From da6514a04a0761f973bb7591a7b41fb235747a3d Mon Sep 17 00:00:00 2001
From: Tim Ruffing <crypto@timruffing.de>
Date: Wed, 6 Jul 2022 15:10:34 +0200
Subject: [PATCH 2/3] config: Introduce DEBUG_CONFIG macro for debug output of
 config

---
 src/ecmult.h     | 8 ++++++++
 src/ecmult_gen.h | 9 +++++++++
 src/util.h       | 5 +++++
 3 files changed, 22 insertions(+)

diff --git a/src/ecmult.h b/src/ecmult.h
index 37c73662f9c88..e28c60250671a 100644
--- a/src/ecmult.h
+++ b/src/ecmult.h
@@ -13,7 +13,15 @@
 
 #ifndef ECMULT_WINDOW_SIZE
 #  define ECMULT_WINDOW_SIZE 15
+#  ifdef DEBUG_CONFIG
+#     pragma message DEBUG_CONFIG_MSG("ECMULT_WINDOW_SIZE undefined, assuming default value")
+#  endif
 #endif
+
+#ifdef DEBUG_CONFIG
+#  pragma message DEBUG_CONFIG_DEF(ECMULT_WINDOW_SIZE)
+#endif
+
 /* Noone will ever need more than a window size of 24. The code might
  * be correct for larger values of ECMULT_WINDOW_SIZE but this is not
  * tested.
diff --git a/src/ecmult_gen.h b/src/ecmult_gen.h
index 8378b8bf3fa44..a430e8d5d9223 100644
--- a/src/ecmult_gen.h
+++ b/src/ecmult_gen.h
@@ -12,10 +12,19 @@
 
 #ifndef ECMULT_GEN_PREC_BITS
 #  define ECMULT_GEN_PREC_BITS 4
+#  ifdef DEBUG_CONFIG
+#     pragma message DEBUG_CONFIG_MSG("ECMULT_GEN_PREC_BITS undefined, assuming default value")
+#  endif
 #endif
+
+#ifdef DEBUG_CONFIG
+#  pragma message DEBUG_CONFIG_DEF(ECMULT_GEN_PREC_BITS)
+#endif
+
 #if ECMULT_GEN_PREC_BITS != 2 && ECMULT_GEN_PREC_BITS != 4 && ECMULT_GEN_PREC_BITS != 8
 #  error "Set ECMULT_GEN_PREC_BITS to 2, 4 or 8."
 #endif
+
 #define ECMULT_GEN_PREC_G(bits) (1 << bits)
 #define ECMULT_GEN_PREC_N(bits) (256 / bits)
 
diff --git a/src/util.h b/src/util.h
index dac86bd77f228..0921e34f1603a 100644
--- a/src/util.h
+++ b/src/util.h
@@ -16,6 +16,11 @@
 #include <stdio.h>
 #include <limits.h>
 
+#define STR_(x) #x
+#define STR(x) STR_(x)
+#define DEBUG_CONFIG_MSG(x) "DEBUG_CONFIG: " x
+#define DEBUG_CONFIG_DEF(x) DEBUG_CONFIG_MSG(#x "=" STR(x))
+
 typedef struct {
     void (*fn)(const char *text, void* data);
     const void* data;

From c27ae451440bdaf68bf8aaa60edb1f4b4614d492 Mon Sep 17 00:00:00 2001
From: Tim Ruffing <crypto@timruffing.de>
Date: Wed, 6 Jul 2022 15:38:21 +0200
Subject: [PATCH 3/3] config: Remove basic-config.h

It's unused and thus potentially confusing.
---
 Makefile.am        |  1 -
 src/basic-config.h | 17 -----------------
 2 files changed, 18 deletions(-)
 delete mode 100644 src/basic-config.h

diff --git a/Makefile.am b/Makefile.am
index 6eb22455697bf..cc7d91a735ff1 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -58,7 +58,6 @@ noinst_HEADERS += src/hash_impl.h
 noinst_HEADERS += src/field.h
 noinst_HEADERS += src/field_impl.h
 noinst_HEADERS += src/bench.h
-noinst_HEADERS += src/basic-config.h
 noinst_HEADERS += contrib/lax_der_parsing.h
 noinst_HEADERS += contrib/lax_der_parsing.c
 noinst_HEADERS += contrib/lax_der_privatekey_parsing.h
diff --git a/src/basic-config.h b/src/basic-config.h
deleted file mode 100644
index 6f7693cb8fd04..0000000000000
--- a/src/basic-config.h
+++ /dev/null
@@ -1,17 +0,0 @@
-/***********************************************************************
- * Copyright (c) 2013, 2014 Pieter Wuille                              *
- * Distributed under the MIT software license, see the accompanying    *
- * file COPYING or https://www.opensource.org/licenses/mit-license.php.*
- ***********************************************************************/
-
-#ifndef SECP256K1_BASIC_CONFIG_H
-#define SECP256K1_BASIC_CONFIG_H
-
-#ifdef USE_BASIC_CONFIG
-
-#define ECMULT_WINDOW_SIZE 15
-#define ECMULT_GEN_PREC_BITS 4
-
-#endif /* USE_BASIC_CONFIG */
-
-#endif /* SECP256K1_BASIC_CONFIG_H */