floss: Fix build faliure: non-void function does not return a value

Also enabled Werror in build.py and fixed a warning in bt_service.

Bug: 290844854
Bug: 361684591
Tag: #floss
Test: mmm packages/modules/Bluetooth
Test: USE=floss_upstream emerge-nami floss
Flag: EXEMPT, Floss-only changes
Change-Id: If832a37a4bd466b0862ca0c4773919b80239fb2f

4 files changed, 4 insertions, 4 deletions

diff --git a/build.py b/build.py
index ff41424431..1f2a925351 100755
--- a/build.py
+++ b/build.py
@@ -380,7 +380,7 @@ class HostBuild():
             'enable_exceptions': os.environ.get('CXXEXCEPTIONS', 0) == '1',
             'external_cflags': [],
             'external_cxxflags': ["-DNDEBUG"],
-            'enable_werror': False,
+            'enable_werror': True,
         }
 
         if clang:
diff --git a/system/btif/src/bluetooth.cc b/system/btif/src/bluetooth.cc
index 6a9a5728b6..d46d594591 100644
--- a/system/btif/src/bluetooth.cc
+++ b/system/btif/src/bluetooth.cc
@@ -432,7 +432,7 @@ static bool is_profile(const char* p1, const char* p2) {
 #ifdef TARGET_FLOSS
 static int global_hci_adapter = 0;
 
-static int set_adapter_index(int adapter) { global_hci_adapter = adapter; }
+static void set_adapter_index(int adapter) { global_hci_adapter = adapter; }
 int GetAdapterIndex() { return global_hci_adapter; }
 #else
 int GetAdapterIndex() { return 0; } // Unsupported outside of FLOSS
diff --git a/system/gd/rust/linux/service/src/main.rs b/system/gd/rust/linux/service/src/main.rs
index e9700c6bb2..17a0fa1f3b 100644
--- a/system/gd/rust/linux/service/src/main.rs
+++ b/system/gd/rust/linux/service/src/main.rs
@@ -99,7 +99,7 @@ fn main() -> Result<(), Box<dyn Error>> {
     let hci_index = matches.value_of("hci").map_or(0, |idx| idx.parse::<i32>().unwrap_or(0));
 
     // The remaining flags are passed down to Fluoride as is.
-    let mut init_flags: Vec<String> = match matches.values_of("init-flags") {
+    let init_flags: Vec<String> = match matches.values_of("init-flags") {
         Some(args) => args.map(String::from).collect(),
         None => vec![],
     };
diff --git a/system/include/hardware/bluetooth.h b/system/include/hardware/bluetooth.h
index faf67a4bbf..5d7de41006 100644
--- a/system/include/hardware/bluetooth.h
+++ b/system/include/hardware/bluetooth.h
@@ -665,7 +665,7 @@ typedef struct {
   size_t size;
 #ifdef TARGET_FLOSS
   /** set index of the adapter to use */
-  int (*set_adapter_index)(int adapter_index);
+  void (*set_adapter_index)(int adapter_index);
 #endif
 
   /**