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From: "zamazan4ik at tut dot by" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug gcov-profile/112829] New: Dump PGO profiles to a memory buffer
Date: Sun, 03 Dec 2023 05:58:44 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D112829

            Bug ID: 112829
           Summary: Dump PGO profiles to a memory buffer
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: gcov-profile
          Assignee: unassigned at gcc dot gnu.org
          Reporter: zamazan4ik at tut dot by
                CC: marxin at gcc dot gnu.org
  Target Milestone: ---

According to the GCC documentation
(https://gcc.gnu.org/onlinedocs/gcc/Instrumentation-Options.html) the only
option is to dump PGO profiles to a filesystem. I am looking for an option =
to
dump PGO profiles into a memory buffer. LLVM infrastructure has such an abi=
lity
- it's documented here:
https://clang.llvm.org/docs/SourceBasedCodeCoverage.html#using-the-profilin=
g-runtime-without-a-filesystem
. If GCC has such an ability too - would be great if it would be described
somewhere in the Instrumentation documentation (or in any other better plac=
e in
your opinion).

The use case for having this is simple - in some systems, a filesystem can =
be
read-only (e.g. due to security concerns) or even not enough to handle the =
PGO
profile. With the memory approach, we will be able to collect PGO profiles =
and
then deliver and expose them via other interfaces like HTTP or MQTT.

I guess some related information can be found here
(https://gcc.gnu.org/git/?p=3Dgcc.git;a=3Dblob;f=3Dlibgcc/libgcov-profiler.=
c) but I
am not sure.=