depends: remove `FORCE_USE_SYSTEM_CLANG` & native_llvm #29188

Always use the system Clang when compiling for macOS. Removes the native_llvm package. Simplifies #21778 (which should also fix the RISC-V macOS cross build).

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Conflicts

Reviewers, this pull request conflicts with the following ones:

• #25573 ([POC] guix: produce a fully -static-pie bitcoind by fanquake)
• #25391 (guix: Use LTO to build releases by fanquake)
• #21778 (build: LLD based macOS toolchain by fanquake)

If you consider this pull request important, please also help to review the conflicting pull requests. Ideally, start with the one that should be merged first.

Concept ACK.

which should also fix the RISC-V macOS cross build

I think that is currently failing due to a bug in the llvm upstream build system (https://github.com/bitcoin/bitcoin/pull/28880#issuecomment-1846869958)

Other than that:

Nice!

I think that is currently failing due to a bug in the llvm upstream build system (https://github.com/bitcoin/bitcoin/pull/28880#issuecomment-1846869958)

Right, I was referring to this failure, #29078 (comment), where we can't compile cctools on RISC-V, because it just isn't supported.

Expecting that macOS cross-compiling CI job will fail and we need to reapply https://github.com/bitcoin/bitcoin/commit/05aca093819be276ac7d648472c6ed5c7d235cc5.

It seems the *__native_toolchain variables are no longer needed:

diff --git a/depends/Makefile b/depends/Makefile
index 319c3498df..8f33b7defa 100644
--- a/depends/Makefile
+++ b/depends/Makefile
@@ -186,7 +186,6 @@ all_packages = $(packages) $(native_packages)
 meta_depends = Makefile funcs.mk builders/default.mk hosts/default.mk hosts/$(host_os).mk builders/$(build_os).mk
 
 $(host_arch)_$(host_os)_native_binutils?=$($(host_os)_native_binutils)
-$(host_arch)_$(host_os)_native_toolchain?=$($(host_os)_native_toolchain)
 
 include funcs.mk
 
diff --git a/depends/builders/darwin.mk b/depends/builders/darwin.mk
index 8ed82b276d..7663a25ac3 100644
--- a/depends/builders/darwin.mk
+++ b/depends/builders/darwin.mk
@@ -22,7 +22,6 @@ darwin_NM:=$(shell xcrun -f nm)
 darwin_INSTALL_NAME_TOOL:=$(shell xcrun -f install_name_tool)
 darwin_DSYMUTIL:=$(shell xcrun -f dsymutil)
 darwin_native_binutils=
-darwin_native_toolchain=
 
 x86_64_darwin_CFLAGS += -arch x86_64
 x86_64_darwin_CXXFLAGS += -arch x86_64
diff --git a/depends/funcs.mk b/depends/funcs.mk
index 987be4e611..d1db87305f 100644
--- a/depends/funcs.mk
+++ b/depends/funcs.mk
@@ -47,7 +47,7 @@ endef
 
 define int_get_build_id
 $(eval $(1)_dependencies += $($(1)_$(host_arch)_$(host_os)_dependencies) $($(1)_$(host_os)_dependencies))
-$(eval $(1)_all_dependencies:=$(call int_get_all_dependencies,$(1),$($($(1)_type)_native_toolchain) $($($(1)_type)_native_binutils) $($(1)_dependencies)))
+$(eval $(1)_all_dependencies:=$(call int_get_all_dependencies,$(1),$($($(1)_type)_native_binutils) $($(1)_dependencies)))
 $(foreach dep,$($(1)_all_dependencies),$(eval $(1)_build_id_deps+=$(dep)-$($(dep)_version)-$($(dep)_recipe_hash)))
 $(eval $(1)_build_id_long:=$(1)-$($(1)_version)-$($(1)_recipe_hash)-$(release_type) $($(1)_build_id_deps) $($($(1)_type)_id))
 $(eval $(1)_build_id:=$(shell echo -n "$($(1)_build_id_long)" | $(build_SHA256SUM) | cut -c-$(HASH_LENGTH)))
@@ -288,5 +288,5 @@ $(foreach package,$(all_packages),$(eval $(call int_config_attach_build_config,$
 #create build targets
 $(foreach package,$(all_packages),$(eval $(call int_add_cmds,$(package))))
 
-#special exception: if a toolchain package exists, all non-native packages depend on it
-$(foreach package,$(packages),$(eval $($(package)_extracted): |$($($(host_arch)_$(host_os)_native_toolchain)_cached) $($($(host_arch)_$(host_os)_native_binutils)_cached) ))
+#special exception: if a native binutils package exists, all non-native packages depend on it
+$(foreach package,$(packages),$(eval $($(package)_extracted): |$($($(host_arch)_$(host_os)_native_binutils)_cached) ))
diff --git a/depends/hosts/darwin.mk b/depends/hosts/darwin.mk
index baaeadf49f..667793d7f6 100644
--- a/depends/hosts/darwin.mk
+++ b/depends/hosts/darwin.mk
@@ -7,7 +7,6 @@ LD64_VERSION=711
 OSX_SDK=$(SDK_PATH)/Xcode-$(XCODE_VERSION)-$(XCODE_BUILD_ID)-extracted-SDK-with-libcxx-headers
 
 darwin_native_binutils=native_cctools
-darwin_native_toolchain=
 
 # We can't just use $(shell command -v clang) because GNU Make handles builtins
 # in a special way and doesn't know that `command` is a POSIX-standard builtin

Concept ACK

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Guix builds (on x86_64)

Pulled back in the commit to fix Qt for Clang < 17.

I'm just going to squash this back into #21778, and get it done together. The changes (combined with lld) are now working.