fix(build): link llama-common-base so CUDA/SYCL source builds link

crates/llama-sys/build.rs

@@ -672,6 +672,12 @@ fn build_from_source(source_dir: &Path, out_dir: &Path, manifest_dir: &Path) {
     build_common_bridge(source_dir, manifest_dir, false);
     emit_common_link_deps(&build_dir);
     emit_install_link_search_paths(&install_dir);
+    // b9837 compiles build-info (llama_build_number(), llama_commit(),
+    // llama_build_info(), and the LLAMA_BUILD_* globals) into a separate
+    // `llama-common-base` archive that libllama-common depends on but that cmake
+    // does not install, so the install-dir scan above misses it. Link it
+    // explicitly — it must come after llama-common, which references the symbols.
+    emit_build_info_link_deps(&build_dir);
     if use_cuda {
         emit_cuda_link_deps();
     }
@@ -950,6 +956,24 @@ fn has_static_lib(dir: &Path, name: &str) -> bool {
     dir.join(format!("lib{name}.a")).exists() || dir.join(format!("{name}.lib")).exists()
 }
 
+/// Link the `llama-common-base` static archive, which holds the generated
+/// build-info symbols (`llama_build_number()`, `llama_commit()`,
+/// `llama_build_info()`, and the `LLAMA_BUILD_*` globals). Since b9837 these
+/// live in their own archive that libllama-common depends on but that cmake does
+/// not install, so the install-dir scan misses them. Emitting this after the
+/// install libs keeps it after llama-common on the link line, which is required
+/// because llama-common references these symbols.
+fn emit_build_info_link_deps(build_dir: &Path) {
+    let common_dir = build_dir.join("common");
+    if has_static_lib(&common_dir, "llama-common-base") {
+        println!(
+            "cargo:rustc-link-search=native={}",
+            common_dir.to_string_lossy()
+        );
+        println!("cargo:rustc-link-lib=static=llama-common-base");
+    }
+}
+
 fn emit_common_link_deps(build_dir: &Path) {
     let common_dir = build_dir.join("common");
     if has_static_lib(&common_dir, "common") {

crates/llama-sys/src/autocommit_common_bridge.cpp

@@ -15,16 +15,11 @@
 #include "log.h"
 #include "sampling.h"
 
-// common.h defines a global `build_info` string derived from these variables.
-// In this integration path libcommon.a is linked directly from the build tree
-// (where build_info object may not be installed), so provide safe fallbacks.
-// When using prebuilt binary releases, libllama-common already provides these.
-#ifndef LLAMA_CPP_PREBUILT
-int LLAMA_BUILD_NUMBER = 0;
-const char * LLAMA_COMMIT = "unknown";
-const char * LLAMA_COMPILER = "unknown";
-const char * LLAMA_BUILD_TARGET = "unknown";
-#endif
+// build-info symbols (llama_build_number(), llama_commit(), the LLAMA_BUILD_*
+// globals, ...) are provided by libllama-common at link time: from the prebuilt
+// libllama-common.so for binary releases, and from the static llama-common-base
+// archive for source builds (linked explicitly in build.rs). Defining fallbacks
+// here would collide with those real definitions, so we don't.
 
 struct autocommit_common_config {
     common_params params;