Commit 4d1c5d698fffe9684b72bcd72d60dfd758eb0ccd | zig

author	Alex Rønne Petersen <alex@alexrp.com> 2026-09-17 07:47:23+02:00
committer	Alex Rønne Petersen <alex@alexrp.com> 2026-09-17 15:27:52+02:00
log	4d1c5d698fffe9684b72bcd72d60dfd758eb0ccd
tree	a07564106cf49745876b6e6ab06786ed50631882
parent	edad096b772d58bc39d227b0ba4d13b641ca99e6
signature	Signed by SSH key SHA256:7B/LJ7bpR1eX8aCXSr4mtd5M45VMPKcx9zY8e95b5QM

std.zig.system: turn an assumption in detectNativeCpuAndFeatures() into an assert

1 files changed, 8 insertions(+), 11 deletions(-)

lib
- std
  - zig
    system.zig

lib/std/zig/system.zig+8-11

 @@ -375,15 +375,13 @@ pub fn resolveTargetQuery(io: Io, query: Target.Query) DetectError!Target {
     var cpu = switch (query.cpu_model) {
         .native => detectNativeCpuAndFeatures(io, query_cpu_arch),
-        .baseline => Target.Cpu.baseline(query_cpu_arch, os),
+        .baseline => null,
         .determined_by_arch_os => if (query.cpu_arch == null)
             detectNativeCpuAndFeatures(io, query_cpu_arch)
         else
-            Target.Cpu.baseline(query_cpu_arch, os),
+            null,
         .explicit => |model| model.toCpu(query_cpu_arch),
-    } orelse backup_cpu_detection: {
+    } orelse Target.Cpu.baseline(query_cpu_arch, os);
-        break :backup_cpu_detection Target.Cpu.baseline(query_cpu_arch, os);
-    };
     // For x86, we need to populate some CPU feature flags depending on architecture
     // and mode:
 @@ -536,12 +534,11 @@ fn updateCpuFeatures(
 }
 fn detectNativeCpuAndFeatures(io: Io, cpu_arch: Target.Cpu.Arch) ?Target.Cpu {
-    // Here we switch on a comptime value rather than `cpu_arch`. This is valid because `cpu_arch`,
+    const family = builtin.target.cpu.arch.family();
-    // although it is a runtime value, is guaranteed to be one of the architectures in the set
+    assert(cpu_arch.family() == family);
-    // of the respective switch prong.
+    switch (family) {
-    switch (builtin.cpu.arch) {
+        .loongarch => return @import("system/loongarch.zig").detectNativeCpuAndFeatures(cpu_arch),
-        .loongarch32, .loongarch64 => return @import("system/loongarch.zig").detectNativeCpuAndFeatures(cpu_arch),
+        .x86 => return @import("system/x86.zig").detectNativeCpuAndFeatures(cpu_arch),
-        .x86_64, .x86 => return @import("system/x86.zig").detectNativeCpuAndFeatures(cpu_arch),
         else => {},
     }