DBN_finetune: layer_input used before set

[DGDanforth]

I converted the C code for DBN to Component Pascal and ran its analyzer over the code. It found in DBN_finetune that the variable "layer_input" was used before any values were set for it. Going back to the C code I see that is indeed true. In fact the array is accessed even before it is allocated.

That has got to be a bug.

Here is the C code

void DBN_finetune(DBN* this, int *input, int *label, double lr, int epochs) {
int i, j, m, n, epoch;

int *layer_input;
// int prev_layer_input_size;
int *prev_layer_input;

int *train_X = (int *)malloc(sizeof(int) * this->n_ins);
int *train_Y = (int *)malloc(sizeof(int) * this->n_outs);

for(epoch=0; epoch<epochs; epoch++) {
for(n=0; nN; n++) { // input x1...xN
// initial input
for(m=0; mn_ins; m++) train_X[m] = input[n * this->n_ins + m];
for(m=0; mn_outs; m++) train_Y[m] = label[n * this->n_outs + m];

  // layer input
  for(i=0; i<this->n_layers; i++) {
    if(i == 0) {
      prev_layer_input = (int *)malloc(sizeof(int) * this->n_ins);
      for(j=0; j<this->n_ins; j++) prev_layer_input[j] = train_X[j];
    } else {
      prev_layer_input = (int *)malloc(sizeof(int) * this->hidden_layer_sizes[i-1]);
      for(j=0; j<this->hidden_layer_sizes[i-1]; j++) prev_layer_input[j] = layer_input[j];
      free(layer_input);
    }


    layer_input = (int *)malloc(sizeof(int) * this->hidden_layer_sizes[i]);
    HiddenLayer_sample_h_given_v(&(this->sigmoid_layers[i]), \
                                 prev_layer_input, layer_input);
    free(prev_layer_input);
  }

  LogisticRegression_train(&(this->log_layer), layer_input, train_Y, lr);
}
// lr *= 0.95;

}

free(layer_input);
free(train_X);
free(train_Y);
}