lapack-reference:x64-windows build failure

[spindensity]

Host Environment

• OS: Windows 10 20H1;
• Compiler: MSVC 2019 16.7.1.

To Reproduce
Steps to reproduce the behavior:

vcpkg install clapack:x64-windows
vcpkg install lapack-reference:x64-windows

Failure logs
Console output:

Computing installation plan...
The following packages will be built and installed:
  lapack-reference[blas-select,core,noblas]:x64-windows
Detecting compiler hash for triplet x64-windows...
Starting package 1/1: lapack-reference:x64-windows
Building package lapack-reference[blas-select,core,noblas]:x64-windows...
Could not locate cached archive: C:\Users\spindensity\AppData\Local\vcpkg/archives\a5\a5de68f965aa3b65735ed503659fde01328703ab.zip
-- Using cached D:/Repository/vcpkg/downloads/Reference-LAPACK-lapack-v3.8.0.tar.gz
-- Cleaning sources at D:/Repository/vcpkg/buildtrees/lapack-reference/src/v3.8.0-954f10683f.clean. Use --editable to skip cleaning for the packages you specify.
-- Extracting source D:/Repository/vcpkg/downloads/Reference-LAPACK-lapack-v3.8.0.tar.gz
-- Using source at D:/Repository/vcpkg/buildtrees/lapack-reference/src/v3.8.0-954f10683f.clean
-- The Fortran compiler identification is unknown
-- No Fortran compiler found on the PATH. Using MinGW gfortran!
-- Acquiring MSYS Packages from D:/Repository/vcpkg/downloads/tools/msys2-20200812...
-- Acquiring MSYS Packages... OK
-- Configuring x64-windows
-- Building x64-windows-dbg
-- Building x64-windows-rel
-- Fixing pkgconfig file: D:/Repository/vcpkg/packages/lapack-reference_x64-windows/lib/pkgconfig/blas.pc
-- Fixing pkgconfig file: D:/Repository/vcpkg/packages/lapack-reference_x64-windows/lib/pkgconfig/lapack.pc
-- Fixing pkgconfig file: D:/Repository/vcpkg/packages/lapack-reference_x64-windows/debug/lib/pkgconfig/blas.pc
-- Fixing pkgconfig file: D:/Repository/vcpkg/packages/lapack-reference_x64-windows/debug/lib/pkgconfig/lapack.pc
-- Warning: Could not find a matching pdb file for:
    D:/Repository/vcpkg/packages/lapack-reference_x64-windows/bin/liblapack.dll
    D:/Repository/vcpkg/packages/lapack-reference_x64-windows/debug/bin/liblapack.dll

-- Installing: D:/Repository/vcpkg/packages/lapack-reference_x64-windows/share/lapack-reference/copyright
-- Performing post-build validation
-- Performing post-build validation done
Stored binary cache: C:\Users\spindensity\AppData\Local\vcpkg/archives\a5\a5de68f965aa3b65735ed503659fde01328703ab.zipBuilding package lapack-reference[blas-select,core,noblas]:x64-windows... done
Installing package lapack-reference[blas-select,core,noblas]:x64-windows...
The following files are already installed in D:/Repository/vcpkg/installed/x64-windows and are in conflict with lapack-reference:x64-windows

Installed by clapack:x64-windows
    lib/lapack.lib

Please ensure you're using the latest portfiles with `.\vcpkg update`, then
submit an issue at https://github.com/Microsoft/vcpkg/issues including:
  Package: lapack-reference:x64-windows
  Vcpkg version: 2020.06.15-nohash

Additionally, attach any relevant sections from the log files above.

Additional context
Vcpkg fails to install lapack-reference:x64-windows because lapack.lib has already been installed by clapack:x64-windows and is in conflict with lapack-reference:x64-windows.

[MVoz]

why do you need two libraries at the same time?

[JackBoosY]

These two ports are conflict with each other.

[spindensity]

why do you need two libraries at the same time?

Here's the story:

I use dlib package to do some machine learning tasks. This package depended on clapack before da839ba on windows. After that commit, it does not depend on clapack but lapack now. vcpkg upgrade never remove the clapack package but installs the new dependency lapack and makes the conflict happen.

Removing the clapack manually could solve the problem, but I think it should be reported as a bug.

[JackBoosY]

I think if we detect the conflict, we should add an error message at least.