diff --git a/internal/cbm/extract_defs.c b/internal/cbm/extract_defs.c
index bfff34fb..63e77b21 100644
--- a/internal/cbm/extract_defs.c
+++ b/internal/cbm/extract_defs.c
@@ -23,7 +23,8 @@
 // Tree traversal limits.
 enum {
     TEMPLATE_DEPTH_LIMIT = 4,
-    DECLARATOR_DEPTH_LIMIT = 8,
+    DECLARATOR_DEPTH_LIMIT = CBM_DECLARATOR_DEPTH_LIMIT, // shared define in helpers.h
+
     EXPORT_ANCESTOR_DEPTH = 4,
     DECORATOR_SCAN_LIMIT = 3,
     C_RETURN_WALK_DEPTH = 5,
@@ -457,27 +458,6 @@ static TSNode resolve_func_name_fp(TSNode node, CBMLanguage lang, const char *ki
     return null_node;
 }
 
-// Check if a node type is a terminal C declarator name.
-static bool is_c_terminal_name(const char *dk) {
-    return strcmp(dk, "identifier") == 0 || strcmp(dk, "field_identifier") == 0 ||
-           strcmp(dk, "operator_name") == 0 || strcmp(dk, "operator_cast") == 0 ||
-           strcmp(dk, "destructor_name") == 0;
-}
-
-// Resolve name from a C++ qualified_identifier/scoped_identifier.
-static TSNode resolve_qualified_name(TSNode decl) {
-    static const char *name_kinds[] = {"operator_name", "operator_cast",    "destructor_name",
-                                       "identifier",    "field_identifier", NULL};
-    for (const char **k = name_kinds; *k; k++) {
-        TSNode found = cbm_find_child_by_kind(decl, *k);
-        if (!ts_node_is_null(found)) {
-            return found;
-        }
-    }
-    TSNode null_node = {0};
-    return null_node;
-}
-
 // C++/CUDA: out-of-line method definitions name the function with a qualified
 // declarator (`Foo::bar`, or `ns::Foo::bar`). Return the immediate enclosing
 // class name (the scope segment directly left of the function name, e.g. "Foo"),
@@ -528,30 +508,6 @@ static char *cpp_out_of_line_parent_class(CBMArena *a, TSNode node, const char *
     return (text && text[0]) ? text : NULL;
 }
 
-// Resolve function name from C/C++/CUDA/GLSL declarator chain.
-static TSNode resolve_c_declarator_name(TSNode node) {
-    TSNode decl = ts_node_child_by_field_name(node, TS_FIELD("declarator"));
-    for (int depth = 0; depth < DECLARATOR_DEPTH_LIMIT && !ts_node_is_null(decl); depth++) {
-        const char *dk = ts_node_type(decl);
-        if (is_c_terminal_name(dk)) {
-            return decl;
-        }
-        if (strcmp(dk, "qualified_identifier") == 0 || strcmp(dk, "scoped_identifier") == 0) {
-            return resolve_qualified_name(decl);
-        }
-        TSNode inner = ts_node_child_by_field_name(decl, TS_FIELD("declarator"));
-        if (ts_node_is_null(inner) && ts_node_named_child_count(decl) > 0) {
-            inner = ts_node_named_child(decl, 0);
-        }
-        if (ts_node_is_null(inner)) {
-            break;
-        }
-        decl = inner;
-    }
-    TSNode null_node = {0};
-    return null_node;
-}
-
 // R: resolve function_definition name from parent binary_operator lhs.
 static TSNode resolve_r_func_name(TSNode node) {
     TSNode parent = ts_node_parent(node);
@@ -675,7 +631,7 @@ static TSNode resolve_func_name_c_family(TSNode *node_ptr, CBMLanguage lang, con
          lang == CBM_LANG_GLSL || lang == CBM_LANG_HLSL || lang == CBM_LANG_ISPC ||
          lang == CBM_LANG_SLANG) &&
         strcmp(kind, "function_definition") == 0) {
-        return resolve_c_declarator_name(*node_ptr);
+        return cbm_resolve_c_declarator_name_node(*node_ptr);
     }
     TSNode null_node = {0};
     return null_node;
diff --git a/internal/cbm/extract_unified.c b/internal/cbm/extract_unified.c
index 7274158f..f65a64be 100644
--- a/internal/cbm/extract_unified.c
+++ b/internal/cbm/extract_unified.c
@@ -101,6 +101,10 @@ static TSNode resolve_func_name_node(TSNode node) {
     if (ts_node_is_null(name_node) && strcmp(ts_node_type(node), "function_declaration") == 0) {
         name_node = cbm_find_child_by_kind(node, "simple_identifier");
     }
+    /* C/C++/CUDA/GLSL: function_definition name lives in the declarator chain. */
+    if (ts_node_is_null(name_node) && strcmp(ts_node_type(node), "function_definition") == 0) {
+        name_node = cbm_resolve_c_declarator_name_node(node);
+    }
     return name_node;
 }
 
diff --git a/internal/cbm/helpers.c b/internal/cbm/helpers.c
index 1efa6b81..c34be9b7 100644
--- a/internal/cbm/helpers.c
+++ b/internal/cbm/helpers.c
@@ -717,7 +717,52 @@ TSNode cbm_find_enclosing_func(TSNode node, CBMLanguage lang) {
     return null_node;
 }
 
-// Get the name of a function node (basic: try "name" field)
+// Check if a node type is a terminal C declarator name.
+static bool is_c_terminal_name(const char *dk) {
+    return strcmp(dk, "identifier") == 0 || strcmp(dk, "field_identifier") == 0 ||
+           strcmp(dk, "operator_name") == 0 || strcmp(dk, "operator_cast") == 0 ||
+           strcmp(dk, "destructor_name") == 0;
+}
+
+// Resolve name from a C++ qualified_identifier/scoped_identifier.
+static TSNode resolve_qualified_name(TSNode decl) {
+    static const char *name_kinds[] = {"operator_name", "operator_cast",    "destructor_name",
+                                       "identifier",    "field_identifier", NULL};
+    for (const char **k = name_kinds; *k; k++) {
+        TSNode found = cbm_find_child_by_kind(decl, *k);
+        if (!ts_node_is_null(found)) {
+            return found;
+        }
+    }
+    TSNode null_node = {0};
+    return null_node;
+}
+
+// Resolve function name from C/C++/CUDA/GLSL declarator chain. Shared canonical
+// implementation — see the header for the full rationale (#438).
+TSNode cbm_resolve_c_declarator_name_node(TSNode func_node) {
+    TSNode decl = ts_node_child_by_field_name(func_node, TS_FIELD("declarator"));
+    for (int depth = 0; depth < CBM_DECLARATOR_DEPTH_LIMIT && !ts_node_is_null(decl); depth++) {
+        const char *dk = ts_node_type(decl);
+        if (is_c_terminal_name(dk)) {
+            return decl;
+        }
+        if (strcmp(dk, "qualified_identifier") == 0 || strcmp(dk, "scoped_identifier") == 0) {
+            return resolve_qualified_name(decl);
+        }
+        TSNode inner = ts_node_child_by_field_name(decl, TS_FIELD("declarator"));
+        if (ts_node_is_null(inner) && ts_node_named_child_count(decl) > 0) {
+            inner = ts_node_named_child(decl, 0);
+        }
+        if (ts_node_is_null(inner)) {
+            break;
+        }
+        decl = inner;
+    }
+    TSNode null_node = {0};
+    return null_node;
+}
+
 static const char *func_node_name(CBMArena *a, TSNode func_node, const char *source,
                                   CBMLanguage lang) {
     // Wolfram: set_delayed_top/set_top/set_delayed/set — LHS is apply(user_symbol("f"), ...)
@@ -752,6 +797,13 @@ static const char *func_node_name(CBMArena *a, TSNode func_node, const char *sou
             }
         }
     }
+    // C/C++/CUDA/GLSL: function_definition carries its name in the declarator chain.
+    if (strcmp(ts_node_type(func_node), "function_definition") == 0) {
+        TSNode dn = cbm_resolve_c_declarator_name_node(func_node);
+        if (!ts_node_is_null(dn)) {
+            return cbm_node_text(a, dn, source);
+        }
+    }
     return NULL;
 }
 
diff --git a/internal/cbm/helpers.h b/internal/cbm/helpers.h
index ea8154d4..35d10892 100644
--- a/internal/cbm/helpers.h
+++ b/internal/cbm/helpers.h
@@ -36,6 +36,20 @@ const char *cbm_enclosing_func_qn(CBMArena *a, TSNode node, CBMLanguage lang, co
 // Cached version: uses ctx->ef_cache to avoid repeated parent-chain walks.
 const char *cbm_enclosing_func_qn_cached(CBMExtractCtx *ctx, TSNode node);
 
+// Max declarator-chain descent depth for C/C++/CUDA/GLSL function-name
+// resolution. Single source of truth — extract_defs.c's DECLARATOR_DEPTH_LIMIT
+// is derived from this so the three extractors cannot drift.
+#define CBM_DECLARATOR_DEPTH_LIMIT 8
+
+// Resolve the function-name node for a C/C++/CUDA/GLSL `function_definition`.
+// Such nodes have no `name` field — the name is nested in the declarator chain
+// (pointer/function/parenthesized/array declarators wrap it; out-of-line method
+// definitions name it with a qualified_identifier). Descends the `declarator`
+// field to the innermost name node and returns it, or a null node if none is
+// found. Shared by the defs, calls, and unified extractors so all three agree on
+// enclosing-function attribution — drift between private copies caused #438.
+TSNode cbm_resolve_c_declarator_name_node(TSNode func_node);
+
 // Find a child node by kind string.
 TSNode cbm_find_child_by_kind(TSNode parent, const char *kind);
 
diff --git a/tests/test_extraction.c b/tests/test_extraction.c
index d06b2a50..9aba9dc7 100644
--- a/tests/test_extraction.c
+++ b/tests/test_extraction.c
@@ -1787,6 +1787,31 @@ TEST(wolfram_caller_attribution) {
     PASS();
 }
 
+/* Issue #438: a C function_definition has no `name` field — the name lives in the
+ * declarator chain. Calls inside a C function must be attributed to the enclosing
+ * function, not the module. Pre-fix, enclosing_func_qn fell back to the module QN. */
+TEST(c_caller_attribution) {
+    CBMFileResult *r = extract("int helper(int x) { return x; }\n"
+                               "int caller(void) { return helper(1); }\n",
+                               CBM_LANG_C, "t", "main.c");
+    ASSERT_NOT_NULL(r);
+    ASSERT_FALSE(r->has_error);
+    ASSERT_GT(r->calls.count, 0);
+    int saw_helper = 0;
+    for (int i = 0; i < r->calls.count; i++) {
+        if (strcmp(r->calls.items[i].callee_name, "helper") == 0) {
+            saw_helper = 1;
+            /* enclosing_func_qn must be the function, NOT empty and NOT the module QN. */
+            ASSERT_NOT_NULL(r->calls.items[i].enclosing_func_qn);
+            ASSERT_FALSE(strcmp(r->calls.items[i].enclosing_func_qn, "") == 0);
+            ASSERT_FALSE(strcmp(r->calls.items[i].enclosing_func_qn, "t.main") == 0);
+        }
+    }
+    ASSERT(saw_helper);
+    cbm_free_result(r);
+    PASS();
+}
+
 /* --- Wolfram parse (simple assignment) --- */
 TEST(wolfram_parse) {
     CBMFileResult *r = extract("x = 42;\ny = x + 1;\n", CBM_LANG_WOLFRAM, "t", "simple.wl");
@@ -3091,6 +3116,7 @@ SUITE(extraction) {
     RUN_TEST(wolfram_function_extended);
     RUN_TEST(wolfram_call);
     RUN_TEST(wolfram_caller_attribution);
+    RUN_TEST(c_caller_attribution);
     RUN_TEST(wolfram_parse);
     RUN_TEST(wolfram_import);
     RUN_TEST(wolfram_nested_def);