Fix the Android build.

tests/android/MiniaudioTester/app/build.gradle.kts

@@ -15,6 +15,12 @@ android {
         versionName = "1.0"
 
         testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
+
+        externalNativeBuild {
+            cmake {
+                cppFlags += "-Wall -Wextra -pedantic"
+            }
+        }
     }
 
     buildTypes {

tests/android/MiniaudioTester/app/src/main/cpp/native-lib.cpp

@@ -34,6 +34,8 @@ static void data_callback(ma_device* pDevice, void* pFramesOut, const void* pFra
     auto* pAudioState = (audio_state_t*)pDevice->pUserData;
     assert(pAudioState != nullptr);
 
+    (void)pFramesIn;
+
     ma_waveform_read_pcm_frames(&pAudioState->waveform, pFramesOut, frameCount, nullptr);
 }
 
@@ -56,6 +58,8 @@ Java_io_miniaud_miniaudiotester_MainActivity_UninitializeAudio(JNIEnv *env, jobj
     pAudioState->hasError = false;
     pAudioState->errorMessage = "";
 
+    (void)env;
+
     return (jlong)pAudioState;
 }
 
@@ -114,6 +118,8 @@ Java_io_miniaud_miniaudiotester_MainActivity_PlayAudio(JNIEnv *env, jobject, jlo
         audio_state_set_error(pAudioState, (std::string("Failed to start device. ") + ma_result_description(result)).c_str());
     }
 
+    (void)env;
+
     return (jlong)pAudioState;
 }
 
@@ -137,6 +143,8 @@ Java_io_miniaud_miniaudiotester_MainActivity_PauseAudio(JNIEnv *env, jobject, jl
         }
     }
 
+    (void)env;
+
     return (jlong)pAudioState;
 }
 
@@ -149,6 +157,8 @@ Java_io_miniaud_miniaudiotester_MainActivity_HasAudioError(JNIEnv *env, jobject,
         return true;
     }
 
+    (void)env;
+
     return pAudioState->hasError;
 }