coredata: Allow setting suproject options from the default_options of

the superproject

This only allows the super project to do this, and not for subprojects
to affect each other, as that would create race conditions and just be
really difficult to make work without a two pass interpreter. This
should probably be deprecated in favor of the default_options argument
to subproject() anyway.

Fixes mesonbuild#7573

mesonbuild/coredata.py

@@ -779,7 +779,9 @@ def make_key(key: str) -> str:
         # split arguments that can be set now, and those that cannot so they
         # can be set later, when they've been initialized.
         for k, v in default_options.items():
-            if k.startswith(lang_prefixes):
+            if ':' in k:
+                continue
+            elif k.startswith(lang_prefixes):
                 lang, key = k.split('_', 1)
                 for machine in MachineChoice:
                     if key not in env.compiler_options[machine][lang]:
@@ -808,11 +810,20 @@ def make_key(key: str) -> str:
         for k, v in default_options.items():
             if k in BUILTIN_OPTIONS and not BUILTIN_OPTIONS[k].yielding:
                 continue
+
+            subp = subproject
+            if ':' in k:
+                # We don't honor subproject options from one subproject to
+                # another, only from the superproject
+                if subproject:
+                    continue
+
+                subp, k = k.split(':')
             for machine in MachineChoice:
                 if machine is MachineChoice.BUILD and not self.is_cross_build():
                     continue
-                if k not in env.meson_options[machine][subproject]:
-                    env.meson_options[machine][subproject][k] = v
+                if k not in env.meson_options[machine][subp]:
+                    env.meson_options[machine][subp][k] = v
 
         self.set_options(options, subproject=subproject)
 

test cases/common/230 persubproject options/meson.build

@@ -1,6 +1,7 @@
 project('persubproject options', 'c',
   default_options : ['default_library=both',
                      'werror=true',
+                     'sub1:werror=false',
                      'warning_level=3'])
 
 assert(get_option('default_library') == 'both', 'Parent default_library should be "both"')

test cases/common/230 persubproject options/subprojects/sub1/meson.build

@@ -3,6 +3,7 @@ project('sub1', 'c',
 
 assert(get_option('default_library') == 'both', 'Should inherit parent project default_library')
 assert(get_option('warning_level') == '0')
+assert(get_option('werror') == false)
 
 # Check it build both by calling a method only both_libraries target implement
 lib = library('lib1', 'foo.c')