Bug 1693723 - Avoid bootstrapping when an explicit path is given for tools. r=firefox-build-system-reviewers,mhentges

This changes things such that setting e.g. NASM=/usr/bin/nasm will avoid
bootstrapping nasm even when bootstrapping is enabled.

This is not applied to CC/CXX/HOST_CC/HOST_CXX because things are more
complicated.

This also simplifies how check_prog is called for a bootstrapped tool,
and avoids the repetition of when.

CBINDGEN handling needs the pattern being applied manually because it
currently doesn't use check_prog. Once --enable-bootstrap=install
becomes the default on developer builds, it will be possible to simplify
this.

Differential Revision: https://phabricator.services.mozilla.com/D105718

build/moz.configure/bindgen.configure

@@ -47,9 +47,16 @@ def check_cbindgen_version(cbindgen, fatal=False):
     )
 
 
+# Similar behavior to what check_prog does.
+has_cbindgen_input = depends("CBINDGEN", when=cbindgen_is_needed)(lambda x: x)
+bootstrap_cbindgen = depends(cbindgen_is_needed, has_cbindgen_input)(
+    lambda n, i: n and not i
+)
+
+
 @depends_if(
     "CBINDGEN",
-    bootstrap_search_path("cbindgen"),
+    bootstrap_search_path("cbindgen", when=bootstrap_cbindgen),
     rust_search_path,
     when=cbindgen_is_needed,
 )

build/moz.configure/checks.configure

@@ -93,6 +93,11 @@ def checking(what, callback=None):
 #   that will cause the given path(s) to be searched rather than $PATH. Input
 #   paths may either be individual paths or delimited by os.pathsep, to allow
 #   passing $PATH (for example) as an element.
+# - `bootstrap` is a path relative to the bootstrap root path (e.g ~/.mozbuild)
+#   where to find the program if it's bootstrapped.
+#
+# - `bootstrap_search_path` is not an argument that users of the template are
+#   supposed to pass. See the override of check_prog in top-level moz.configure.
 #
 # The simplest form is:
 #   check_prog('PROG', ('a', 'b'))
@@ -108,7 +113,9 @@ def check_prog(
     input=None,
     allow_missing=False,
     paths=None,
+    bootstrap=None,
     when=None,
+    bootstrap_search_path=None,
 ):
     if input is not None:
         # Wrap input with type checking and normalization.
@@ -140,6 +147,20 @@ def check_prog(
     paths = dependable(paths)
     allow_missing = dependable(allow_missing)
 
+    if bootstrap:
+        if input is var:
+            # A when is needed when depending on an option, so normalize
+            # to a function that can used without.
+            has_input = depends(input, when=when)(lambda x: x)
+        else:
+            has_input = input
+        # We don't want to bootstrap when an explicit value was given as input.
+        if when:
+            bootstrap_when = depends(when, has_input)(lambda w, i: w and not i)
+        else:
+            bootstrap_when = depends(has_input)(lambda i: not i)
+        paths = bootstrap_search_path(bootstrap, paths, when=bootstrap_when)
+
     # Avoid displaying the "Checking for" message when the inputs are such
     # that we don't actually want anything to be checked. It is a bit
     # convoluted because of how `when` works.

build/moz.configure/node.configure

@@ -8,7 +8,11 @@ option("--disable-nodejs", help="Require Node.js to build")
 option(env="NODEJS", nargs=1, help="Path to nodejs")
 
 
-@depends("--enable-nodejs", "NODEJS", bootstrap_search_path("node"))
+@depends(
+    "--enable-nodejs",
+    "NODEJS",
+    bootstrap_search_path("node", when=depends("NODEJS")(lambda x: not x)),
+)
 @checking(
     "for nodejs", callback=lambda x: "%s (%s)" % (x.path, x.str_version) if x else "no"
 )

moz.configure

@@ -391,22 +391,35 @@ def bootstrap_path(path, **kwargs):
 
 
 @template
-def bootstrap_search_path(path, **kwargs):
+def bootstrap_search_path(path, paths=original_path, **kwargs):
     @depends(
         bootstrap_path(path, **kwargs),
         bootstrap_search_path_order,
+        paths,
         original_path,
     )
-    def bootstrap_search_path(path, order, original_path):
+    def bootstrap_search_path(path, order, paths, original_path):
+        if paths is None:
+            paths = original_path
         if not path:
-            return original_path
+            return paths
         if order == "prepend":
-            return [path] + original_path
-        return original_path + [path]
+            return [path] + paths
+        return paths + [path]
 
     return bootstrap_search_path
 
 
+# The execution model of the configure sandbox doesn't allow for
+# check_prog to use bootstrap_search_path directly because check_prog
+# comes first, so we use a trick to allow it. No use of check_prog
+# happening before here won't allow bootstrap.
+@template
+def check_prog(*args, **kwargs):
+    kwargs["bootstrap_search_path"] = bootstrap_search_path
+    return check_prog(*args, **kwargs)
+
+
 @depends(target, host)
 def want_wine(target, host):
     return target.kernel == "WINNT" and host.kernel != "WINNT"
@@ -417,7 +430,7 @@ wine = check_prog(
     ["wine64", "wine"],
     allow_missing=True,
     when=want_wine,
-    paths=bootstrap_search_path("wine/bin", when=want_wine),
+    bootstrap="wine/bin",
 )
 check_prog("WGET", ("wget",), allow_missing=True)
 

toolkit/moz.configure

@@ -1943,7 +1943,7 @@ nasm = check_prog(
     "NASM",
     ["nasm"],
     allow_missing=True,
-    paths=bootstrap_search_path("nasm", when=need_nasm),
+    bootstrap="nasm",
     when=need_nasm,
 )
 
@@ -2083,7 +2083,7 @@ set_config("MOZ_USING_WASM_SANDBOXING", requires_wasm_sandboxing)
 set_define("MOZ_USING_WASM_SANDBOXING", requires_wasm_sandboxing)
 
 with only_when(requires_wasm_sandboxing & compile_environment):
-    lucetc = check_prog("LUCETC", ["lucetc"], paths=bootstrap_search_path("lucetc"))
+    lucetc = check_prog("LUCETC", ["lucetc"], bootstrap="lucetc")
 
     option(
         "--with-wasi-sysroot",
@@ -2333,7 +2333,7 @@ check_prog(
     "DUMP_SYMS",
     ["dump_syms"],
     allow_missing=True,
-    paths=bootstrap_search_path("dump_syms", when=compile_environment),
+    bootstrap="dump_syms",
     when=compile_environment,
 )
 
@@ -2342,7 +2342,7 @@ check_prog(
     "PDBSTR",
     ["pdbstr.exe"],
     allow_missing=True,
-    paths=bootstrap_search_path("pdbstr", when=compile_environment & target_is_windows),
+    bootstrap="pdbstr",
     when=compile_environment & target_is_windows,
 )
 
@@ -2358,9 +2358,7 @@ def allow_missing_winchecksec(automation, c_compiler):
 check_prog(
     "WINCHECKSEC",
     ["winchecksec.exe", "winchecksec"],
-    paths=bootstrap_search_path(
-        "winchecksec", when=compile_environment & target_is_windows
-    ),
+    bootstrap="winchecksec",
     allow_missing=allow_missing_winchecksec,
     when=compile_environment & target_is_windows,
 )