#Conditional watchpoint stops despite specified condition

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frigid ibex
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Hello, I wanted to set a conditional breakpoint, if velocity.x is std::nan. However it appears the std::nan call is not really parsable. So what do I do about this? I get this message from GDB.

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charred mantleBOT
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jagged thunder
# frigid ibex Hello, I wanted to set a conditional breakpoint, if velocity.x is std::nan. Howe...

isnan() is not a C function, but a preprocessor macro, which are not available by default to gdb.

See this blog post that discusses your exact problem:
https://ro-che.info/articles/2020-01-11-gdb-break-on-nan

Break on NaN in gdb

Recently I had to debug a case where, somewhere during a
numerically-intensive computation (solving an ordinary differential
equation), a value would become NaN (“not a number”). This
happens, for example, when taking a logarithm or a square root of a
negative number, dividing 0 by 0, stuff like that. However, I had no
idea where and why NaNs ap...

frigid ibex