transpile: fix zero initializer imports

c2rust-transpile/src/translator/mod.rs

@@ -4174,8 +4174,6 @@ impl<'c> Translation<'c> {
         decl_id: CDeclId,
         type_id: CTypeId,
     ) -> TranslationResult<WithStmts<Box<Expr>>> {
-        self.import_type(type_id);
-
         let name = self.type_converter.borrow().resolve_decl_name(decl_id);
         let name = name.as_deref().unwrap_or("???");
 
@@ -4190,6 +4188,7 @@ impl<'c> Translation<'c> {
         let func_name = func_name.as_deref().unwrap_or("<none>");
         log::debug!("deferring imports to save them for {name} in {func_name}");
         self.defer_imports();
+        self.import_type(type_id);
 
         let name_decl_id = match self.ast_context.resolve_type_no_typedef(type_id).kind {
             CTypeKind::Typedef(decl_id) => decl_id,

c2rust-transpile/tests/snapshots.rs

@@ -617,6 +617,21 @@ fn test_wide_strings() {
         .run();
 }
 
+#[test]
+fn test_zero_init_typedef_reorg_imports() {
+    let c_path = Path::new("tests/snapshots/zero_init_typedef_reorg.c");
+    let mut cfg = config(Edition2021);
+    cfg.reorganize_definitions = true;
+    cfg.disable_refactoring = true;
+    compile_and_transpile_file(c_path, cfg);
+
+    let rs_path = c_path.with_extension("rs");
+    rustc(&rs_path)
+        .edition(Edition2021)
+        .crate_name("zero_init_typedef_reorg")
+        .run();
+}
+
 // arch-os-specific
 
 #[test]

c2rust-transpile/tests/snapshots/zero_init_typedef_reorg.c

@@ -0,0 +1,25 @@
+typedef struct Stat {
+    int mode;
+    long size;
+} STAT_T;
+
+/* The implicit zero-initializer for the `st` field is the first one created
+ * for `struct Stat`, so it populates the cache. Because the field is spelled
+ * with the typedef, the cached expression is rendered as `STAT_T { ... }`. */
+struct OuterMain {
+    int x;
+    STAT_T st;
+};
+
+static void before_include(void) {
+    struct OuterMain o = {0};
+    (void)o;
+}
+
+#include "zero_init_typedef_reorg.h"
+
+int main(void) {
+    before_include();
+    after_include();
+    return 0;
+}

c2rust-transpile/tests/snapshots/zero_init_typedef_reorg.h

@@ -0,0 +1,14 @@
+/* Zero-initializing this struct reuses the cached `STAT_T { ... }`
+ * initializer for the `st` field, even though the field is spelled with the
+ * struct tag. The `use STAT_T` this header module needs must therefore be
+ * replayed from the imports cached alongside the initializer; the imports
+ * derived from the type of the hit site only cover `Stat`. */
+struct OuterHeader {
+    int y;
+    struct Stat st;
+};
+
+static void after_include(void) {
+    struct OuterHeader o = {0};
+    (void)o;
+}