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Altera_Forum's avatar
Altera_Forum
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10 years ago

Channel has no point Connection

I just got a weird error when trying to build my OpenCL code with aocl: Error Channel has no point connection: ID= in_channel_a avm_channel_id_in_channel_a_write connection misin, or optimize...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
10 years ago

I seem to have found the issue. When I change the loop from 

for(int i = -1; i < n_steps; ++i)

to 

for(int i = -1; i < (int)n_steps; ++i)

The error disappears.

This means the compiler evaluates "(int)-1 < (uint)0" as false. As a result the entire Loop is optimized away, so in_channel_a for example is never read. I still think this is a compiler error though, does anyone here know what the OpenCL spec says about signed-unsigned comparison?