bench: refactor to use dynamic memory allocation in blas/base/sdot

PR-URL: #10173
Ref: #8643

Reviewed-by: Philipp Burckhardt <pburckhardt@outlook.com>

Author: prajjwalbajpai

lib/node_modules/@stdlib/blas/base/sdot/benchmark/c/benchmark.length.c

@@ -96,12 +96,14 @@ static float rand_float( void ) {
 */
 static double benchmark1( int iterations, int len ) {
 	double elapsed;
-	float x[ len ];
-	float y[ len ];
+	float *x;
+	float *y;
 	float z;
 	double t;
 	int i;
 
+	x = (float *) malloc( len * sizeof( float ) );
+	y = (float *) malloc( len * sizeof( float ) );
 	for ( i = 0; i < len; i++ ) {
 		x[ i ] = ( rand_float()*20000.0f ) - 10000.0f;
 		y[ i ] = ( rand_float()*20000.0f ) - 10000.0f;
@@ -120,6 +122,8 @@ static double benchmark1( int iterations, int len ) {
 	if ( z != z ) {
 		printf( "should not return NaN\n" );
 	}
+	free( x );
+	free( y );
 	return elapsed;
 }
 
@@ -132,12 +136,14 @@ static double benchmark1( int iterations, int len ) {
 */
 static double benchmark2( int iterations, int len ) {
 	double elapsed;
-	float x[ len ];
-	float y[ len ];
+	float *x;
+	float *y;
 	float z;
 	double t;
 	int i;
 
+	x = (float *) malloc( len * sizeof( float ) );
+	y = (float *) malloc( len * sizeof( float ) );
 	for ( i = 0; i < len; i++ ) {
 		x[ i ] = ( rand_float()*20000.0f ) - 10000.0f;
 		y[ i ] = ( rand_float()*20000.0f ) - 10000.0f;
@@ -156,6 +162,8 @@ static double benchmark2( int iterations, int len ) {
 	if ( z != z ) {
 		printf( "should not return NaN\n" );
 	}
+	free( x );
+	free( y );
 	return elapsed;
 }