From 7f37668ba2e813f15f2a444a8dfadc7eb3e5acd4 Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Fri, 28 Jun 2024 17:32:28 +0100
Subject: [PATCH] autotools: Add `--no-undefined` linker option

---
 Makefile.am                  |  2 +-
 build-aux/m4/bitcoin_secp.m4 | 16 ++++++++++++++++
 configure.ac                 |  3 +++
 3 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/Makefile.am b/Makefile.am
index 322e44eaab..57464fa35b 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -98,7 +98,7 @@ endif
 libsecp256k1_la_SOURCES = src/secp256k1.c
 libsecp256k1_la_CPPFLAGS = $(SECP_CONFIG_DEFINES)
 libsecp256k1_la_LIBADD = $(COMMON_LIB) $(PRECOMPUTED_LIB)
-libsecp256k1_la_LDFLAGS = -no-undefined -version-info $(LIB_VERSION_CURRENT):$(LIB_VERSION_REVISION):$(LIB_VERSION_AGE)
+libsecp256k1_la_LDFLAGS = -no-undefined -version-info $(LIB_VERSION_CURRENT):$(LIB_VERSION_REVISION):$(LIB_VERSION_AGE) $(SECP_LIB_LDFLAGS)
 
 noinst_PROGRAMS =
 if USE_BENCHMARK
diff --git a/build-aux/m4/bitcoin_secp.m4 b/build-aux/m4/bitcoin_secp.m4
index 048267fa6e..6036fa04d5 100644
--- a/build-aux/m4/bitcoin_secp.m4
+++ b/build-aux/m4/bitcoin_secp.m4
@@ -77,6 +77,22 @@ AC_DEFUN([SECP_TRY_APPEND_CFLAGS], [
   AC_SUBST($2)
 ])
 
+dnl SECP_TRY_APPEND_LDFLAGS(flags, VAR)
+dnl Append flags to VAR if a linker accepts them.
+AC_DEFUN([SECP_TRY_APPEND_LDFLAGS], [
+  AC_MSG_CHECKING([if linker supports $1])
+  SECP_TRY_APPEND_LDFLAGS_saved_LDFLAGS="$LDFLAGS"
+  LDFLAGS="$1 $LDFLAGS"
+  AC_LINK_IFELSE([AC_LANG_PROGRAM()], [flag_works=yes], [flag_works=no])
+  AC_MSG_RESULT($flag_works)
+  LDFLAGS="$SECP_TRY_APPEND_LDFLAGS_saved_LDFLAGS"
+  if test x"$flag_works" = x"yes"; then
+    $2="$$2 $1"
+  fi
+  unset flag_works
+  AC_SUBST($2)
+])
+
 dnl SECP_SET_DEFAULT(VAR, default, default-dev-mode)
 dnl Set VAR to default or default-dev-mode, depending on whether dev mode is enabled
 AC_DEFUN([SECP_SET_DEFAULT], [
diff --git a/configure.ac b/configure.ac
index adae189787..a57b9c84f8 100644
--- a/configure.ac
+++ b/configure.ac
@@ -131,6 +131,8 @@ AC_DEFUN([SECP_TRY_APPEND_DEFAULT_CFLAGS], [
 ])
 SECP_TRY_APPEND_DEFAULT_CFLAGS(SECP_CFLAGS)
 
+SECP_TRY_APPEND_LDFLAGS([-Wl,--no-undefined], [SECP_LIB_LDFLAGS])
+
 ###
 ### Define config arguments
 ###
@@ -486,6 +488,7 @@ echo "  CC                      = $CC"
 echo "  CPPFLAGS                = $CPPFLAGS"
 echo "  SECP_CFLAGS             = $SECP_CFLAGS"
 echo "  CFLAGS                  = $CFLAGS"
+echo "  SECP_LIB_LDFLAGS        = $SECP_LIB_LDFLAGS"
 echo "  LDFLAGS                 = $LDFLAGS"
 
 if test x"$print_msan_notice" = x"yes"; then