lisa._kmod: Make toolchain selection reproducible

FIX

Remove impact of set iteration order from the toolchain selection
process.

lisa/_kmod.py

@@ -1463,7 +1463,7 @@ def _resolve_toolchain(cls, abi, build_conf, target=None):
         env = cls._make_toolchain_env_from_conf(build_conf)
 
         def priority_to(cc):
-            def prio(_cc):
+            def prio(_cc, _cross_compile):
                 prio = 0 if cc in _cc.name else 1
                 return (prio, prio == 0)
             return prio
@@ -1490,7 +1490,7 @@ def version_key(version):
                             abs(clang_version - version)
                         )
 
-                    def cc_priority(cc):
+                    def cc_priority(cc, cross_compile):
                         def prio(cc):
                             if 'clang' in cc.name:
                                 version = re.search(r'[0-9]+', cc.name)
@@ -1550,7 +1550,7 @@ def prio(cc):
 
         # The format of "ccs" dict is:
         # (CC=, CROSS_COMPILE=): <binary name>
-        ccs = {
+        ccs = [
             *(
                 (Path(f'clang-{i}'), cross_compile)
                 # Cover for the next 10 years starting from 2021
@@ -1568,31 +1568,31 @@ def prio(cc):
                 (Path('gcc'), cross_compile)
                 for cross_compile in cross_compiles
             ),
-        }
+        ]
 
         if 'CC' in make_vars:
             _cc = _make_vars_cc(make_vars)
-            ccs = {
+            ccs = [
                 (_cc, cross_compile)
                 for cross_compile in cross_compiles
-            }
+            ]
 
         if 'LLVM' in make_vars:
             llvm = make_vars['LLVM']
             _cc = _make_vars_cc(make_vars, 'clang')
             llvm_version = llvm if llvm.startswith('-') else None
             if _cc.name == 'clang' and llvm_version:
                 _cc = _cc.with_name(f'{_cc.name}{llvm_version}')
-                ccs = {
+                ccs = [
                     (_cc, cross_compile)
                     for cross_compile in cross_compiles
-                }
+                ]
 
         # Give priority for the toolchain the kernel seem to have been compiled
         # with
         def key(item):
             (cc, cross_compile) = item
-            return cc_priority(cc)
+            return cc_priority(cc, cross_compile)
 
         ccs = sorted(ccs, key=key)
 
@@ -1687,9 +1687,9 @@ def version_cmd(cc, cross_compile):
         if cross_compile is None:
             raise ValueError(f'Could not detect which CROSS_COMPILE value to use')
 
-        ideal_cc, _ = ccs[0]
-        cc_is_perfect = cc_priority(cc)[1]
-        if str(cc) != str(ideal_cc) or not cc_is_perfect:
+        ideal_cc, ideal_cross_compile = ccs[0]
+        cc_is_perfect = cc_priority(cc, cross_compile)[1]
+        if str(cc) != str(ideal_cc) or ideal_cross_compile != cross_compile or not cc_is_perfect:
             logger.warning(f'Could not find ideal CC={ideal_cc} but found CC={cc} instead. Results may vary from working fine to crashing the kernel')
 
         return (cc, cross_compile, cc_key)