Fix compare_and_swap call in bitmap #2
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old_val with the value of loc (the pointer it self). Passing loc as first argument makes the compiler instantiate compare_and_swap with T=int * but then the function call __sync_bool_compare_and_swap as: __sync_bool_compare_and_swap(&x, old_val, new_val); This means that the type of the first argument is int ** which is wrong. There is one more issue still to address. The family of functions __sync_* works only with primitive types and templates in platform_atomics.h do not address this issue.
sbeamer
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Jun 28, 2015
Fix compare_and_swap call in bitmap
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Thanks! This is definitely a bug and was due to me switching over to the newer platform_atomics.h API but using the older bitmap class. I'm sorry for any loss of productivity this caused. |
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BFS was hanging here because the compare_and_swap template was comparing
old_val with the value of loc (the pointer it self).
Passing loc as first argument makes the compiler instantiate compare_and_swap
with T=int * but then the function call __sync_bool_compare_and_swap as:
__sync_bool_compare_and_swap(&x, old_val, new_val);
This means that the type of the first argument is int ** which is wrong.
There is one more issue still to address. The family of functions _sync*
works only with primitive types and templates in platform_atomics.h do not
address this issue.