build-script: Don't emit build commands for LLVM when --build-llvm set to false

Author: AnthonyLatsis

utils/swift_build_support/swift_build_support/products/cmake_product.py

@@ -70,7 +70,9 @@ def build_with_cmake(self, build_targets, build_type, build_args,
                            + self.args.extra_cmake_options + [self.source_dir],
                            env=env)
 
-        if not self.args.skip_build or self.product_name() == "llvm":
+        if not self.args.skip_build or (
+             self.product_name() == "llvm" and self.args._build_llvm
+        ):
             cmake_opts = [self.build_dir, "--config", build_type]
 
             if self.args.cmake_generator == "Xcode":

utils/swift_build_support/swift_build_support/products/llvm.py

@@ -216,20 +216,11 @@ def build(self, host_target):
                 # space/time efficient than -g on that platform.
                 llvm_cmake_options.define('LLVM_USE_SPLIT_DWARF:BOOL', 'YES')
 
-        build_targets = ['all']
-
-        if self.args.llvm_ninja_targets_for_cross_compile_hosts and \
-           self.is_cross_compile_target(host_target):
-            build_targets = (self.args.llvm_ninja_targets_for_cross_compile_hosts)
-        elif self.args.llvm_ninja_targets:
-            build_targets = (self.args.llvm_ninja_targets)
-
-        # indicating we don't want to build LLVM should
-        # override any custom ninja target we specified
         if not self.args._build_llvm:
-            build_targets = ['clean']
-
-        if self.args.skip_build or not self.args.build_llvm:
+            # Indicating we don't want to build LLVM at all should
+            # override everything.
+            build_targets = []
+        elif self.args.skip_build or not self.args.build_llvm:
             # We can't skip the build completely because the standalone
             # build of Swift depends on these.
             build_targets = ['llvm-tblgen', 'clang-resource-headers',
@@ -248,6 +239,14 @@ def build(self, host_target):
                     'llvm-nm',
                     'llvm-size'
                 ])
+        else:
+            build_targets = ['all']
+
+            if self.args.llvm_ninja_targets_for_cross_compile_hosts and \
+               self.is_cross_compile_target(host_target):
+                build_targets = (self.args.llvm_ninja_targets_for_cross_compile_hosts)
+            elif self.args.llvm_ninja_targets:
+                build_targets = (self.args.llvm_ninja_targets)
 
         if self.args.host_libtool:
             llvm_cmake_options.define('CMAKE_LIBTOOL', self.args.host_libtool)