From 59c881ff2f0d5cff4dee0577ac4dbc109a6a5f77 Mon Sep 17 00:00:00 2001
From: Alexander Medvednikov <alexander@medvednikov.com>
Date: Tue, 21 Apr 2026 17:15:47 +0300
Subject: [PATCH] cgen: fix $embed_file not compiling on win10 with microsoft
 compiler (fixes #12035)

---
 .gitignore                                     |  5 +++++
 vlib/v/gen/c/embed.v                           |  4 +++-
 .../c/testdata/embed_issue_12035.c.must_have   |  3 +++
 vlib/v/gen/c/testdata/embed_issue_12035.out    |  1 +
 vlib/v/gen/c/testdata/embed_issue_12035.vv     | 18 ++++++++++++++++++
 5 files changed, 30 insertions(+), 1 deletion(-)
 create mode 100644 vlib/v/gen/c/testdata/embed_issue_12035.c.must_have
 create mode 100644 vlib/v/gen/c/testdata/embed_issue_12035.out
 create mode 100644 vlib/v/gen/c/testdata/embed_issue_12035.vv

diff --git a/.gitignore b/.gitignore
index 51d04b1eb..1243de1a5 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,6 +7,11 @@
 !vlib/v/gen/c/testdata/nested_unary_minus_regression.vv
 !vlib/v/gen/c/testdata/nested_unary_minus_regression.out
 
+# unignore c codegen testdata files
+!vlib/v/gen/c/testdata/*.vv
+!vlib/v/gen/c/testdata/*.out
+!vlib/v/gen/c/testdata/*.c.must_have
+
 # unignore vlib/x/markdown
 !vlib/x/markdown/**
 
diff --git a/vlib/v/gen/c/embed.v b/vlib/v/gen/c/embed.v
index e3ed4560a..26fb33da2 100644
--- a/vlib/v/gen/c/embed.v
+++ b/vlib/v/gen/c/embed.v
@@ -142,6 +142,8 @@ fn (mut g Gen) gen_embedded_data() {
 	// maybe we need to write to separate files or have an external tool for large files
 	// like the `rcc` tool in Qt?
 	*/
+	// Declare the index before any generated helper references it, to keep MSVC happy.
+	g.embedded_data.writeln('static const v__embed_file__EmbedFileIndexEntry _v_embed_file_index[];')
 	for i, emfile in g.embedded_files {
 		g.embedded_data.write_string('static const unsigned char _v_embed_blob_${i}[${emfile.bytes.len}] = {\n    ')
 		for j := 0; j < emfile.bytes.len; j++ {
@@ -158,7 +160,7 @@ fn (mut g Gen) gen_embedded_data() {
 		g.embedded_data.writeln('\n};')
 	}
 	g.embedded_data.writeln('')
-	g.embedded_data.writeln('const v__embed_file__EmbedFileIndexEntry _v_embed_file_index[] = {')
+	g.embedded_data.writeln('static const v__embed_file__EmbedFileIndexEntry _v_embed_file_index[] = {')
 	for i, emfile in g.embedded_files {
 		g.embedded_data.writeln('\t{${i}, { .str=(byteptr)("${cestring(emfile.rpath)}"), .len=${emfile.rpath.len}, .is_lit=1 }, { .str=(byteptr)("${cestring(emfile.compression_type)}"), .len=${emfile.compression_type.len}, .is_lit=1 }, (byteptr)_v_embed_blob_${i}},')
 	}
diff --git a/vlib/v/gen/c/testdata/embed_issue_12035.c.must_have b/vlib/v/gen/c/testdata/embed_issue_12035.c.must_have
new file mode 100644
index 000000000..98f362eab
--- /dev/null
+++ b/vlib/v/gen/c/testdata/embed_issue_12035.c.must_have
@@ -0,0 +1,3 @@
+static const v__embed_file__EmbedFileIndexEntry _v_embed_file_index[];
+static const v__embed_file__EmbedFileIndexEntry _v_embed_file_index[] = {
+v__embed_file__EmbedFileData _v_embed_file_metadata(u64 ef_hash) {
diff --git a/vlib/v/gen/c/testdata/embed_issue_12035.out b/vlib/v/gen/c/testdata/embed_issue_12035.out
new file mode 100644
index 000000000..665d1524f
--- /dev/null
+++ b/vlib/v/gen/c/testdata/embed_issue_12035.out
@@ -0,0 +1 @@
+issue-12035
diff --git a/vlib/v/gen/c/testdata/embed_issue_12035.vv b/vlib/v/gen/c/testdata/embed_issue_12035.vv
new file mode 100644
index 000000000..7036e8032
--- /dev/null
+++ b/vlib/v/gen/c/testdata/embed_issue_12035.vv
@@ -0,0 +1,18 @@
+// vtest vflags: -prod -no-skip-unused
+const embedded_version = get_version()
+
+fn get_version() string {
+	data := $embed_file('embed_issue_12035.vv')
+	for line in data.to_string().split_into_lines() {
+		x := line.trim_space()
+		if x.starts_with('// version:') {
+			return x.all_after("'").all_before("'")
+		}
+	}
+	return '<unknown>'
+}
+
+// version: 'issue-12035'
+fn main() {
+	println(embedded_version)
+}
-- 
2.39.5