BoostDetectToolset.cmake doesn't match version number generated with b2

[cdglove]

When I build my libraries on MingW using GCC 9.2, I get library names as follows:

libboost_serialization-mgw92-mt-x64-1_73.a

But, when I try to consume Boost from cmake using something like:

find_package( Boost CONFIG REQUIRED serialization)

I get an error like:

Found package configuration file:
[cmake] 
[cmake]     C:/Users/cdglo/src/cmn/boost/stage/lib/cmake/boost_serialization-1.73.0/boost_serialization-config.cmake
[cmake] 
[cmake]   but it set boost_serialization_FOUND to FALSE so package
[cmake]   "boost_serialization" is considered to be NOT FOUND.  Reason given by
[cmake]   package:
[cmake] 
[cmake]   No suitable build variant has been found.
[cmake] 
[cmake]   The following variants have been tried and rejected:
[cmake] 
[cmake] 
[cmake]   * libboost_serialization-mgw92-mt-d-x64-1_73.a (mgw92, detected mgw9, set
[cmake]   Boost_COMPILER to override)
[cmake] 
[cmake]   * libboost_serialization-mgw92-mt-x64-1_73.a (mgw92, detected mgw9, set
[cmake]   Boost_COMPILER to override)
[cmake] 
[cmake]   * libboost_serialization-vc142-mt-gd-x64-1_73.lib (vc142, detected mgw9,
[cmake]   set Boost_COMPILER to override)
[cmake] 
[cmake]   * libboost_serialization-vc142-mt-x64-1_73.lib (vc142, detected mgw9, set
[cmake]   Boost_COMPILER to override)
[cmake] 
[cmake] Call Stack (most recent call first):
[cmake]   C:/Users/cdglo/src/cmn/boost/stage/lib/cmake/Boost/BoostConfig.cmake:185 (boost_find_component)
[cmake]   CMakeLists.txt:23 (find_package)
[cmake] 

The error being here:

mgw92, detected mgw9

I found that removing this code from BoostDetectToolset fixes this issue for me, but I'm not sure sure why that code is there.

elseif(MINGW)

  set(BOOST_DETECTED_TOOLSET "mgw")

  # if(_BOOST_COMPILER_VERSION_MAJOR GREATER 4)
  #  set(_BOOST_COMPILER_VERSION_MINOR)**
  # endif()

[pdimov]

BoostDetectedToolset is actually right here, mgw9 is the correct tag; b2 is wrong. I'll prepare a PR against Boost.Build.

[cdglove]

That makes sense. I can rename the libraries in the mean time.