Merge d1bf035017 into f845fa04a0

Closes #21815.

lib/std/Build.zig

@@ -1982,6 +1982,10 @@ pub const Dependency = struct {
             }
         }
         return found orelse {
+            if (d.builder.graph.needed_lazy_dependencies.entries.len != 0) {
+                // The artifact might become available after missing lazy dependencies have been resolved.
+                process.exit(3);
+            }
             for (d.builder.install_tls.step.dependencies.items) |dep_step| {
                 const inst = dep_step.cast(Step.InstallArtifact) orelse continue;
                 log.info("available artifact: '{s}'", .{inst.artifact.name});

lib/std/debug/MemoryAccessor.zig

@@ -48,7 +48,8 @@ fn read(ma: *MemoryAccessor, address: usize, buf: []u8) bool {
                 switch (linux.E.init(bytes_read)) {
                     .SUCCESS => return bytes_read == buf.len,
                     .FAULT => return false,
-                    .INVAL, .PERM, .SRCH => unreachable, // own pid is always valid
+                    .INVAL, .SRCH => unreachable, // own pid is always valid
+                    .PERM => {}, // Known to happen in containers.
                     .NOMEM => {},
                     .NOSYS => {}, // QEMU is known not to implement this syscall.
                     else => unreachable, // unexpected