diff --git a/configure.ac b/configure.ac
index feb6046f..39ac0a4e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -277,6 +277,7 @@ dnl ================================================================
 
 AX_CHECK_COMPILE_FLAG([-Wmissing-prototypes],    [CFLAGS="-Wmissing-prototypes $CFLAGS"])
 AX_CHECK_COMPILE_FLAG([-Wreturn-type],           [CFLAGS="-Wreturn-type $CFLAGS"])
+AX_CHECK_COMPILE_FLAG([-Wuninitialized],         [CFLAGS="-Wuninitialized $CFLAGS"])
 AX_CHECK_COMPILE_FLAG([-Wunused],                [CFLAGS="-Wunused $CFLAGS"])
 AX_CHECK_COMPILE_FLAG([-Wunused-parameter],      [CFLAGS="-Wunused-parameter $CFLAGS"])
 
diff --git a/src/libespeak-ng/compiledata.c b/src/libespeak-ng/compiledata.c
index 6beb5d79..c114681d 100644
--- a/src/libespeak-ng/compiledata.c
+++ b/src/libespeak-ng/compiledata.c
@@ -2716,7 +2716,7 @@ espeak_ng_STATUS espeak_ng_CompileIntonation(FILE *log, espeak_ng_ERROR_CONTEXT
 	int done_onset = 0;
 	int done_last = 0;
 	int n_preset_tunes = 0;
-	int found;
+	int found = 0;
 	int tune_number = 0;
 	FILE *f_out;
 	TUNE *tune_data;