From 3d9b41ecc02a69daa19df2bc850d60bf9917b724 Mon Sep 17 00:00:00 2001
From: fanquake <fanquake@gmail.com>
Date: Thu, 13 Feb 2020 14:21:32 +0800
Subject: [PATCH] build: add --enable-determinism configure flag

If used, this will enable additional compile / link time flags
that will make subsequent builds of bitcoind determinisitic.
---
 configure.ac | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/configure.ac b/configure.ac
index d0fcf48713a..35e5dc1fe77 100644
--- a/configure.ac
+++ b/configure.ac
@@ -262,6 +262,13 @@ AC_ARG_ENABLE([gprof],
     [enable_gprof=$enableval],
     [enable_gprof=no])
 
+dnl Pass compiler & liner flags that make builds deterministic
+AC_ARG_ENABLE([determinism],
+    [AS_HELP_STRING([--enable-determinism],
+                    [Enable compilation flags that make builds deterministic (default is no)])],
+    [enable_determinism=$enableval],
+    [enable_determinism=no])
+
 dnl Turn warnings into errors
 AC_ARG_ENABLE([werror],
     [AS_HELP_STRING([--enable-werror],
@@ -764,6 +771,12 @@ if test x$TARGET_OS = xdarwin; then
   AX_CHECK_LINK_FLAG([[-Wl,-bind_at_load]], [HARDENED_LDFLAGS="$HARDENED_LDFLAGS -Wl,-bind_at_load"])
 fi
 
+if test x$enable_determinism = xyes; then
+  if test x$TARGET_OS = xwindows; then
+    AX_CHECK_LINK_FLAG([[-Wl,--no-insert-timestamp]], [LDFLAGS="$LDFLAGS -Wl,--no-insert-timestamp"])
+  fi
+fi
+
 AC_CHECK_HEADERS([endian.h sys/endian.h byteswap.h stdio.h stdlib.h unistd.h strings.h sys/types.h sys/stat.h sys/select.h sys/prctl.h sys/sysctl.h vm/vm_param.h sys/vmmeter.h sys/resources.h])
 
 dnl FD_ZERO may be dependent on a declaration of memcpy, e.g. in SmartOS