32-bit int overflow in heap profile

[sporksmith]

Originally golang/go#48580

I'm profiling a long-running program using LD_PRELOAD=/usr/lib/x86_64-linux-gnu/libtcmalloc_and_profiler.so.4 HEAPPROFILE=shadow.heap HEAP_PROFILE_TIME_INTERVAL=180

The initial profiles are parsed fine by pprof, but after a point pprof refuses to parse any subsequent profiles.

Inspecting the profiles themselves, it looks like a 32-bit integer is overflowing.

First line from the last parseable profile:

heap profile: 2237252: 888238604 [2144665071: 188608279238] @ heapprofile

And from the first un-parseable profile:

heap profile: 2250136: 892383061 [-2147316050: 188867582594] @ heapprofile

I've confirmed that editing the files to change the negative number to a positive number allows pprof to parse it. It also works if I put a number there too large to be represented by a 32-bit int, suggesting that pprof supports a larger integer size.

[ckennelly]

I think this issue corresponds to https://github.com/gperftools/gperftools.

[sporksmith]

@ckennelly moved; thanks