[build-script] Add the installation prefix to the toolchain path

In several places, it was assumed to be /usr and hard-coded to that. This makes sure
the installation prefix actually passed in is used.

Author: finagolfin

utils/swift_build_support/swift_build_support/products/pythonkit.py

@@ -32,7 +32,7 @@ def should_build(self, host_target):
     def build(self, host_target):
         toolchain_path = targets.toolchain_path(self.args.install_destdir,
                                                 self.args.install_prefix)
-        swiftc = os.path.join(toolchain_path, 'usr', 'bin', 'swiftc')
+        swiftc = os.path.join(toolchain_path, 'bin', 'swiftc')
 
         # FIXME: this is a workaround for CMake <3.16 which does not correctly
         # generate the build rules if you are not in the build directory.  As a
@@ -52,7 +52,7 @@ def build(self, host_target):
                 self.toolchain.cmake,
                 '-G', 'Ninja',
                 '-D', 'BUILD_SHARED_LIBS=YES',
-                '-D', 'CMAKE_INSTALL_PREFIX={}/usr'.format(
+                '-D', 'CMAKE_INSTALL_PREFIX={}'.format(
                     self.install_toolchain_path()),
                 '-D', 'CMAKE_MAKE_PROGRAM={}'.format(self.toolchain.ninja),
                 '-D', 'CMAKE_Swift_COMPILER={}'.format(swiftc),

utils/swift_build_support/swift_build_support/products/swiftpm.py

@@ -32,7 +32,7 @@ def run_bootstrap_script(self, action, host_target, additional_params=[]):
         script_path = os.path.join(
             self.source_dir, 'Utilities', 'bootstrap')
         toolchain_path = self.install_toolchain_path()
-        swiftc = os.path.join(toolchain_path, "usr", "bin", "swiftc")
+        swiftc = os.path.join(toolchain_path, "bin", "swiftc")
 
         # FIXME: We require llbuild build directory in order to build. Is
         # there a better way to get this?

utils/swift_build_support/swift_build_support/products/tensorflow.py

@@ -32,7 +32,7 @@ def should_build(self, host_target):
     def build(self, host_target):
         toolchain_path = targets.toolchain_path(self.args.install_destdir,
                                                 self.args.install_prefix)
-        swiftc = os.path.join(toolchain_path, 'usr', 'bin', 'swiftc')
+        swiftc = os.path.join(toolchain_path, 'bin', 'swiftc')
 
         # FIXME: this is a workaround for CMake <3.16 which does not correctly
         # generate the build rules if you are not in the build directory.  As a
@@ -52,7 +52,7 @@ def build(self, host_target):
                 self.toolchain.cmake,
                 '-G', 'Ninja',
                 '-D', 'BUILD_SHARED_LIBS=YES',
-                '-D', 'CMAKE_INSTALL_PREFIX={}/usr'.format(
+                '-D', 'CMAKE_INSTALL_PREFIX={}'.format(
                     self.install_toolchain_path()),
                 '-D', 'CMAKE_MAKE_PROGRAM={}'.format(self.toolchain.ninja),
                 '-D', 'CMAKE_Swift_COMPILER={}'.format(swiftc),

utils/swift_build_support/swift_build_support/targets.py

@@ -284,5 +284,7 @@ def toolchain_path(install_destdir, install_prefix):
     built_toolchain_path = install_destdir
     if platform.system() == 'Darwin':
         # The prefix is an absolute path, so concatenate without os.path.
-        built_toolchain_path += darwin_toolchain_prefix(install_prefix)
+        built_toolchain_path += darwin_toolchain_prefix(install_prefix) + "/usr"
+    else:
+        built_toolchain_path += install_prefix
     return built_toolchain_path