From 80970cc2a04c532ede12170e3dba68f24d4ee6a3 Mon Sep 17 00:00:00 2001
From: Aaron Paterson <apaterson@pm.me>
Date: Fri, 23 Oct 2026 02:29:35 -0500
Subject: [PATCH] fix(sqlite-vec.h.tmpl): give SQLITE_VEC_API no __attribute__
 under MSVC in static builds

With -DSQLITE_VEC_STATIC the template defines SQLITE_VEC_API as
__attribute__((visibility("default"))) on every compiler. MSVC has no
__attribute__, so a static build with it stops at the header's declaration
of sqlite3_vec_init(); with MSVC 19.44 on windows-2022:

    cl /c /W4 /Ivendor/ /O2 /DSQLITE_CORE /DSQLITE_VEC_STATIC sqlite-vec.c

    sqlite-vec.h(33): error C2143: syntax error: missing ')' before '('
    sqlite-vec.h(33): error C2091: function returns function

The loadable build, which CI compiles with cl.exe, takes the _WIN32 branch
and is unaffected.

The static branch now applies the attribute only under GCC and Clang outside
Windows, the guard asg017/sqlite-vec#340 uses, and defines SQLITE_VEC_API
empty otherwise. With GCC and Clang the static objects are byte-identical
before and after. sqlite-vec.h regenerates from the template at release, as
it does for the template's other changes.
---
 CHANGELOG.md      | 1 +
 sqlite-vec.h.tmpl | 4 ++++
 2 files changed, 5 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index da5f90d1..f7680ce7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,7 @@
 
 ### Fixed
 
+- Compiling `sqlite-vec.c` with MSVC and `-DSQLITE_VEC_STATIC` succeeds; in that build `sqlite-vec.h` declared `sqlite3_vec_init()` with `__attribute__((visibility("default")))` on every compiler, and MSVC, which has no `__attribute__`, stopped with `error C2143`. GCC and Clang builds are unchanged.
 - A KNN query that takes its query vector, `k`, or `mmr_lambda` from another table of a join now uses it. `select v.rowid from p join v on v.embedding match ? and v.k = p.k` failed with `A LIMIT or 'k = ?' constraint is required`; the same join with `v.k = 3 and v.mmr_lambda = p.lambda` returned no rows; and `select v.rowid from v join p on p.id = v.tag where v.embedding match p.vector and v.k = 2`, with `p.id` an integer primary key, could return no rows. These joins now run one KNN per row of the other table, so a filter on the `vec0` table whose value comes from that table applies before the k nearest rows are chosen. Ported in part from the unmerged [vlasky#14](https://github.com/vlasky/sqlite-vec/pull/14) ([asg017#331](https://github.com/asg017/sqlite-vec/pull/331)), which also applies filters whose value comes from a joined table before the k nearest rows are chosen; that part is not ported, and ARCHITECTURE.md's idxStr section says why.
 
 ## [2.1.1] - 2026-10-09
diff --git a/sqlite-vec.h.tmpl b/sqlite-vec.h.tmpl
index 33d977e4..e150c0d1 100644
--- a/sqlite-vec.h.tmpl
+++ b/sqlite-vec.h.tmpl
@@ -8,8 +8,12 @@
 #endif
 
 #ifdef SQLITE_VEC_STATIC
+#if defined(__GNUC__) && !defined(_WIN32)
 #define SQLITE_VEC_API __attribute__((visibility("default")))
 #else
+#define SQLITE_VEC_API
+#endif
+#else
 #ifdef _WIN32
 #define SQLITE_VEC_API __declspec(dllexport)
 #else