From b31ad1d2eec8aeef59a71751f65779bb5812592a Mon Sep 17 00:00:00 2001
From: Alexander Medvednikov <alexander@medvednikov.com>
Date: Thu, 26 Feb 2026 11:35:38 +0300
Subject: [PATCH] cgen: import submodule of third-party module (fixes #14548)

---
 vlib/v/gen/c/fn.v                                   |  3 ++-
 .../path4/.cache/README.md                          |  4 ++++
 .../path4/hunam6/voak/foo/foo.v                     |  1 +
 .../path4/hunam6/voak/v.mod                         |  3 +++
 .../path4/hunam6/voak/voak.v                        |  5 +++++
 .../submodule_of_third_party_main.vv                |  1 +
 .../vmodules_overrides_test.v                       | 13 +++++++++++++
 7 files changed, 29 insertions(+), 1 deletion(-)
 create mode 100644 vlib/v/tests/multiple_paths_in_vmodules/path4/.cache/README.md
 create mode 100644 vlib/v/tests/multiple_paths_in_vmodules/path4/hunam6/voak/foo/foo.v
 create mode 100644 vlib/v/tests/multiple_paths_in_vmodules/path4/hunam6/voak/v.mod
 create mode 100644 vlib/v/tests/multiple_paths_in_vmodules/path4/hunam6/voak/voak.v
 create mode 100644 vlib/v/tests/multiple_paths_in_vmodules/submodule_of_third_party_main.vv

diff --git a/vlib/v/gen/c/fn.v b/vlib/v/gen/c/fn.v
index 9cc8e34d4..7e76b9186 100644
--- a/vlib/v/gen/c/fn.v
+++ b/vlib/v/gen/c/fn.v
@@ -113,9 +113,10 @@ fn (mut g Gen) fn_decl(node ast.FnDecl) {
 		// TODO: true for not just "builtin"
 		// TODO: clean this up
 		mod := if g.is_builtin_mod { 'builtin' } else { node.name.all_before_last('.') }
+		module_built_short := g.module_built.all_after_last('/').all_after_last('.')
 		// for now dont skip generic functions as they are being marked as static
 		// when -usecache is enabled, until a better solution is implemented.
-		if ((mod != g.module_built && node.mod != g.module_built.after('/'))
+		if ((mod != g.module_built && node.mod != g.module_built && node.mod != module_built_short)
 			|| should_bundle_module) && node.generic_names.len == 0 {
 			// Skip functions that don't have to be generated for this module.
 			// println('skip bm ${node.name} mod=${node.mod} module_built=${g.module_built}')
diff --git a/vlib/v/tests/multiple_paths_in_vmodules/path4/.cache/README.md b/vlib/v/tests/multiple_paths_in_vmodules/path4/.cache/README.md
new file mode 100644
index 000000000..0ad0cc1a7
--- /dev/null
+++ b/vlib/v/tests/multiple_paths_in_vmodules/path4/.cache/README.md
@@ -0,0 +1,4 @@
+This folder contains cached build artifacts from the V build system.
+You can safely delete it, if it is getting too large.
+It will be recreated the next time you compile something with V.
+You can change its location with the VCACHE environment variable.
diff --git a/vlib/v/tests/multiple_paths_in_vmodules/path4/hunam6/voak/foo/foo.v b/vlib/v/tests/multiple_paths_in_vmodules/path4/hunam6/voak/foo/foo.v
new file mode 100644
index 000000000..49525808b
--- /dev/null
+++ b/vlib/v/tests/multiple_paths_in_vmodules/path4/hunam6/voak/foo/foo.v
@@ -0,0 +1 @@
+module foo
diff --git a/vlib/v/tests/multiple_paths_in_vmodules/path4/hunam6/voak/v.mod b/vlib/v/tests/multiple_paths_in_vmodules/path4/hunam6/voak/v.mod
new file mode 100644
index 000000000..d254554b9
--- /dev/null
+++ b/vlib/v/tests/multiple_paths_in_vmodules/path4/hunam6/voak/v.mod
@@ -0,0 +1,3 @@
+Module {
+	name: 'hunam6.voak'
+}
diff --git a/vlib/v/tests/multiple_paths_in_vmodules/path4/hunam6/voak/voak.v b/vlib/v/tests/multiple_paths_in_vmodules/path4/hunam6/voak/voak.v
new file mode 100644
index 000000000..4391e8121
--- /dev/null
+++ b/vlib/v/tests/multiple_paths_in_vmodules/path4/hunam6/voak/voak.v
@@ -0,0 +1,5 @@
+module voak
+
+pub fn hello() string {
+	return 'hello'
+}
diff --git a/vlib/v/tests/multiple_paths_in_vmodules/submodule_of_third_party_main.vv b/vlib/v/tests/multiple_paths_in_vmodules/submodule_of_third_party_main.vv
new file mode 100644
index 000000000..cbca77d73
--- /dev/null
+++ b/vlib/v/tests/multiple_paths_in_vmodules/submodule_of_third_party_main.vv
@@ -0,0 +1 @@
+import hunam6.voak.foo
diff --git a/vlib/v/tests/multiple_paths_in_vmodules/vmodules_overrides_test.v b/vlib/v/tests/multiple_paths_in_vmodules/vmodules_overrides_test.v
index 3bf10b5bb..c27429dd3 100644
--- a/vlib/v/tests/multiple_paths_in_vmodules/vmodules_overrides_test.v
+++ b/vlib/v/tests/multiple_paths_in_vmodules/vmodules_overrides_test.v
@@ -14,6 +14,10 @@ const mainvv = os.join_path(basepath, 'main.vv')
 
 const cmd = '${os.quoted_path(vexe)} run ${os.quoted_path(mainvv)}'
 
+const submodule_mainvv = os.join_path(basepath, 'submodule_of_third_party_main.vv')
+
+const submodule_cmd = '${os.quoted_path(vexe)} ${os.quoted_path(submodule_mainvv)}'
+
 fn test_vexe_is_set() {
 	assert vexe != ''
 	println('vexe: ${vexe}')
@@ -38,3 +42,12 @@ fn test_compiling_with_vmodules_works() {
 	assert res.exit_code == 0, res.output
 	assert res.output.trim_space() == "['x', 'y', 'z']"
 }
+
+fn test_importing_third_party_submodule_works() {
+	os.chdir(vroot) or {}
+	os.setenv('VMODULES', os.join_path(basepath, 'path4'), true)
+	dump(os.getenv('VMODULES'))
+	dump(submodule_cmd)
+	res := os.execute(submodule_cmd)
+	assert res.exit_code == 0, res.output
+}
-- 
2.39.5