Merge bitcoin/bitcoin#23955: build: add support for NetBSD in depends

bcd36e14f0a2b89445f1436094de40696d6ad76c build: correct depends FreeBSD C{XX}FLAGS (fanquake)
7b06ffce9c50110b475c722918c55a14402346a5 build: add NetBSD support to depends (fanquake)

Pull request description:

  Similar to #23948. Doesn't build the Qt package; I haven't looked at doing that yet, but have an assumption that it's going to fail out of the box similar to the FreeBSD build.

  Guix Build:
  ```bash
  ```

ACKs for top commit:
  theuni:
    ACK bcd36e14f0a2b89445f1436094de40696d6ad76c

Tree-SHA512: 9a0946cefbcb9a92dd730b885463f3213e304c8d4b39fea8d831fc013a73d2ef998ca84e384bf45a01fa1449cf5a35eaffaa5b57a9062c2cdda34312d33ec3fc

8 files changed, 44 insertions, 5 deletions

diff --git a/depends/Makefile b/depends/Makefile
index 573115d447..723509c81d 100644
--- a/depends/Makefile
+++ b/depends/Makefile
@@ -77,6 +77,7 @@ full_build_os:=$(subst $(build_arch)-$(build_vendor)-,,$(build))
 build_os:=$(findstring linux,$(full_build_os))
 build_os+=$(findstring darwin,$(full_build_os))
 build_os+=$(findstring freebsd,$(full_build_os))
+build_os+=$(findstring netbsd,$(full_build_os))
 build_os+=$(findstring openbsd,$(full_build_os))
 build_os:=$(strip $(build_os))
 ifeq ($(build_os),)
@@ -89,6 +90,7 @@ full_host_os:=$(subst $(host_arch)-$(host_vendor)-,,$(canonical_host))
 host_os:=$(findstring linux,$(full_host_os))
 host_os+=$(findstring darwin,$(full_host_os))
 host_os+=$(findstring freebsd,$(full_host_os))
+host_os+=$(findstring netbsd,$(full_host_os))
 host_os+=$(findstring openbsd,$(full_host_os))
 host_os+=$(findstring mingw32,$(full_host_os))
 
diff --git a/depends/builders/netbsd.mk b/depends/builders/netbsd.mk
new file mode 100644
index 0000000000..b7cf1f7514
--- /dev/null
+++ b/depends/builders/netbsd.mk
@@ -0,0 +1,2 @@
+build_netbsd_SHA256SUM = shasum -a 256
+build_netbsd_DOWNLOAD = curl --location --fail --connect-timeout $(DOWNLOAD_CONNECT_TIMEOUT) --retry $(DOWNLOAD_RETRIES) -o
diff --git a/depends/hosts/freebsd.mk b/depends/hosts/freebsd.mk
index 307f844331..0a62347b57 100644
--- a/depends/hosts/freebsd.mk
+++ b/depends/hosts/freebsd.mk
@@ -1,11 +1,11 @@
 freebsd_CFLAGS=-pipe
-freebsd_CFLAGS_CXXFLAGS=$(freebsd_CFLAGS)
+freebsd_CXXFLAGS=$(freebsd_CFLAGS)
 
-freebsd_CFLAGS_release_CFLAGS=-O2
-freebsd_CFLAGS_release_CXXFLAGS=$(freebsd_release_CFLAGS)
+freebsd_release_CFLAGS=-O2
+freebsd_release_CXXFLAGS=$(freebsd_release_CFLAGS)
 
-freebsd_CFLAGS_debug_CFLAGS=-O1
-freebsd_CFLAGS_debug_CXXFLAGS=$(freebsd_debug_CFLAGS)
+freebsd_debug_CFLAGS=-O1
+freebsd_debug_CXXFLAGS=$(freebsd_debug_CFLAGS)
 
 ifeq (86,$(findstring 86,$(build_arch)))
 i686_freebsd_CC=clang -m32
diff --git a/depends/hosts/netbsd.mk b/depends/hosts/netbsd.mk
new file mode 100644
index 0000000000..b3e4545a64
--- /dev/null
+++ b/depends/hosts/netbsd.mk
@@ -0,0 +1,31 @@
+netbsd_CFLAGS=-pipe
+netbsd_CXXFLAGS=$(netbsd_CFLAGS)
+
+netbsd_release_CFLAGS=-O2
+netbsd_release_CXXFLAGS=$(netbsd_release_CFLAGS)
+
+netbsd_debug_CFLAGS=-O1
+netbsd_debug_CXXFLAGS=$(netbsd_debug_CFLAGS)
+
+ifeq (86,$(findstring 86,$(build_arch)))
+i686_netbsd_CC=gcc -m32
+i686_netbsd_CXX=g++ -m32
+i686_netbsd_AR=ar
+i686_netbsd_RANLIB=ranlib
+i686_netbsd_NM=nm
+i686_netbsd_STRIP=strip
+
+x86_64_netbsd_CC=gcc -m64
+x86_64_netbsd_CXX=g++ -m64
+x86_64_netbsd_AR=ar
+x86_64_netbsd_RANLIB=ranlib
+x86_64_netbsd_NM=nm
+x86_64_netbsd_STRIP=strip
+else
+i686_netbsd_CC=$(default_host_CC) -m32
+i686_netbsd_CXX=$(default_host_CXX) -m32
+x86_64_netbsd_CC=$(default_host_CC) -m64
+x86_64_netbsd_CXX=$(default_host_CXX) -m64
+endif
+
+netbsd_cmake_system=NetBSD
diff --git a/depends/packages/bdb.mk b/depends/packages/bdb.mk
index 95004f3a22..dc536fd399 100644
--- a/depends/packages/bdb.mk
+++ b/depends/packages/bdb.mk
@@ -11,6 +11,7 @@ $(package)_config_opts=--disable-shared --enable-cxx --disable-replication --ena
 $(package)_config_opts_mingw32=--enable-mingw
 $(package)_config_opts_linux=--with-pic
 $(package)_config_opts_freebsd=--with-pic
+$(package)_config_opts_netbsd=--with-pic
 $(package)_config_opts_openbsd=--with-pic
 $(package)_config_opts_android=--with-pic
 $(package)_cflags+=-Wno-error=implicit-function-declaration
diff --git a/depends/packages/libevent.mk b/depends/packages/libevent.mk
index 78850e583e..748ed510c1 100644
--- a/depends/packages/libevent.mk
+++ b/depends/packages/libevent.mk
@@ -13,6 +13,7 @@ define $(package)_set_vars
   $(package)_config_opts_release=--disable-debug-mode
   $(package)_config_opts_linux=--with-pic
   $(package)_config_opts_freebsd=--with-pic
+  $(package)_config_opts_netbsd=--with-pic
   $(package)_config_opts_openbsd=--with-pic
   $(package)_config_opts_android=--with-pic
   $(package)_cppflags_mingw32=-D_WIN32_WINNT=0x0601
diff --git a/depends/packages/sqlite.mk b/depends/packages/sqlite.mk
index 94bc6dda79..126781ceeb 100644
--- a/depends/packages/sqlite.mk
+++ b/depends/packages/sqlite.mk
@@ -8,6 +8,7 @@ define $(package)_set_vars
 $(package)_config_opts=--disable-shared --disable-readline --disable-dynamic-extensions --enable-option-checking
 $(package)_config_opts_linux=--with-pic
 $(package)_config_opts_freebsd=--with-pic
+$(package)_config_opts_netbsd=--with-pic
 $(package)_config_opts_openbsd=--with-pic
 endef
 
diff --git a/depends/packages/zeromq.mk b/depends/packages/zeromq.mk
index 2d8286ea36..c74ae15b31 100644
--- a/depends/packages/zeromq.mk
+++ b/depends/packages/zeromq.mk
@@ -13,6 +13,7 @@ define $(package)_set_vars
   $(package)_config_opts += --disable-Werror --disable-drafts --enable-option-checking
   $(package)_config_opts_linux=--with-pic
   $(package)_config_opts_freebsd=--with-pic
+  $(package)_config_opts_netbsd=--with-pic
   $(package)_config_opts_openbsd=--with-pic
   $(package)_config_opts_android=--with-pic
   $(package)_cxxflags+=-std=c++17