Mysterious bugs appearing when compiling for release but not debug

Audio Plugins
1

Hi, I’m making a synth plugin using visual studio and juce. It’s still in the early days but I wanted to compile for release and then test it out in ableton. So far I have just been testing within visual studio using “Debug” mode.

However a bug has appeared after I compiled for release that does not appear when compiling for debug.
Basically in my synth I have 4 oscillators with their own envelopes. In Release mode, if I change the sustain level of my oscillator there will be a (very loud)pop once the decay phase is finished. This does not happen for any of my other envelope values and it produces this funny looking waveform:

image
image1394×409 45.8 KB

I am using a look up table for my exponential decay.
Does anyone know what I could do to fix this and why ON EARTH it doesn’t happen when compiling for debug??? I am sure this is not the first bug I will find.

This is my Envelope logic:

float Envelope::process()
{
    if (isRelease)  //RELEASE PHASE
    {
        envelopeValue *= releaseRatio;

        if (envelopeValue <= 0.001f)
            finished = true;
    }
    else
    {
        if (totalTime <= attackTime && attackTime != 0)//ATTACK PHASE
        {
            envelopeValue = totalTime / attackTime;
        }
        else
        {
            if (totalTime < attackTime + decayTime) // DECAY PHASE
            {
                float index = (totalTime - attackTime) * LOOK_UP_TABLE_LENGTH / decayTime;

                float x = exponentialDecayTable[(int)index];
                float x1 = exponentialDecayTable[(int)index + 1];
                float t = index - (int)index;

                envelopeValue = (1 - sustainLevel) * lin_interp(x, x1, t) + sustainLevel;
            }
            else //SUSTAIN PHASE
            {
                envelopeValue = sustainLevel;
            }
        }
    }

    totalTime += timeDelta;

    return envelopeValue;
}

totalTime is a variable that shows the time since the note was pressed essentially.

thanks in advance,
Dario

2

Debug builds don’t perform optimizations, and may pre-fill arrays or other data structures with 0s, which Release builds don’t do, causing Release builds to expose bugs that are there that the Debug build hides. Check your build logs and look for any mention of use of uninitialized variables, and make sure you clear any data arrays that might be used but not filled by the processing.

3

Thank you, it was a problem with my linear interpolation. Presumably because of this line:

                float x1 = exponentialDecayTable[(int)index + 1];

which I uses for linear interpolation.
For some reason compiling for debug did not mind this.