--- COMPILING

This project has begun being ported to Windows, only tcmalloc_minimal
is supported at this time.  A working solution file exists in this
directory:
    gperftools.sln

You can load this solution file into Visual Studio 2015 or
later -- in the latter case, it will automatically convert the files
to the latest format for you.

When you build the solution, it will create a number of unittests,
which you can run by hand (or, more easily, under the Visual Studio
debugger) to make sure everything is working properly on your system.
The binaries will end up in a directory called "debug" or "release" in
the top-level directory (next to the .sln file).

I don't know very much about how to install DLLs on Windows, so you'll
have to figure out that part for yourself.  If you choose to just
re-use the existing .sln, make sure you set the IncludeDir's
appropriately!  Look at the properties for libtcmalloc_minimal.dll.

Note that these systems are set to build in Debug mode by default.
You may want to change them to Release mode.

To use tcmalloc_minimal in your own projects, you should only need to
build the dll and install it someplace, so you can link it into
further binaries.  To use the dll, you need to add the following to
the linker line of your executable:
   "libtcmalloc_minimal.lib" /INCLUDE:"__tcmalloc"

Here is how to accomplish this in Visual Studio 2015:

1) Have your executable depend on the tcmalloc library by selecting
   "Project Dependencies..." from the "Project" menu.  Your executable
   should depend on "libtcmalloc_minimal".

2) Have your executable depend on a tcmalloc symbol -- this is
   necessary so the linker doesn't "optimize out" the libtcmalloc
   dependency -- by right-clicking on your executable's project (in
   the solution explorer), selecting Properties from the pull-down
   menu, then selecting "Configuration Properties" -> "Linker" ->
   "Input".  Then, in the "Force Symbol References" field, enter the
   text "__tcmalloc" (without the quotes).  Be sure to do this for both
   debug and release modes!

You can also link tcmalloc code in statically -- see the example
project tcmalloc_minimal_unittest-static, which does this.  For this
to work, you'll need to add "/D PERFTOOLS_DLL_DECL=" to the compile
line of every perftools .cc file.  You do not need to depend on the
tcmalloc symbol in this case (that is, you don't need to do either
step 1 or step 2 from above).

An alternative to all the above is to statically link your application
with libc, and then replace its malloc with tcmalloc.  This allows you
to just build and link your program normally; the tcmalloc support
comes in a post-processing step.  This is more reliable than the above
technique (which depends on run-time patching, which is inherently
fragile), though more work to set up.  For details, see
   https://groups.google.com/group/google-perftools/browse_thread/thread/41cd3710af85e57b


--- THE HEAP-PROFILER

The heap-profiler has had a preliminary port to Windows but does not
build on Windows by default.  It has not been well tested, and
probably does not work at all when Frame Pointer Optimization (FPO) is
enabled -- that is, in release mode.  The other features of perftools,
such as the cpu-profiler and leak-checker, have not yet been ported to
Windows at all.


--- ISSUES

NOTE ON _MSIZE and _RECALLOC: The tcmalloc version of _msize returns
the size of the region tcmalloc allocated for you -- which is at least
as many bytes you asked for, but may be more.  (btw, these *are* bytes
you own, even if you didn't ask for all of them, so it's correct code
to access all of them if you want.)  Unfortunately, the Windows CRT
_recalloc() routine assumes that _msize returns exactly as many bytes
as were requested.  As a result, _recalloc() may not zero out new
bytes correctly.  IT'S SAFEST NOT TO USE _RECALLOC WITH TCMALLOC.
_recalloc() is a tricky routine to use in any case (it's not safe to
use with realloc, for instance).


I have little experience with Windows programming, so there may be
better ways to set this up than I've done!  If you run across any
problems, please post to the google-perftools Google Group, or report
them on the gperftools Google Code site:
   http://groups.google.com/group/google-perftools
   http://code.google.com/p/gperftools/issues/list

-- craig
-- updated by alk on 31 July 2023

Last modified: 31 July 2023
