Boost FetchContent Extraction Fails on Windows with tar.gz Archive

[nobShinjo]

Description

When using CMake to build a project with Boost as a dependency via FetchContent, the extraction of the tar.gz archive fails on Windows. This issue appears to be related to Windows handling of empty pathnames in tar archives. Switching to the zip archive resolves the issue.

Steps to Reproduce

1. Use the following FetchContent_Declare in a CMake project:

   cmake\boost.cmake

   FetchContent_Declare(
       boost
       URL https://github.com/boostorg/boost/releases/download/boost-1.81.0/boost-1.81.0.tar.gz
       URL_HASH MD5=ffac94fbdd92d6bc70a897052022eeba
   )
   FetchContent_MakeAvailable(boost)

2. Run CMake configuration on a Windows system

   cmake .. -DCMAKE_BUILD_TYPE=Release -DCMAKE_MSVC_RUNTIME_LIBRARY=MultiThreaded -DOPENVDB_CORE_SHARED=OFF -DTBB_TEST=OFF -DCMAKE_CXX_FLAGS="/MT /EHsc" 

3. Observe the extraction error.

Observed Behavior

CMake fails during the extraction step with the following error:

 -- extracting...
       src='C:/***/CoACD/build/_deps/boost-subbuild/boost-populate-prefix/src/boost-1.81.0.tar.gz'     
       dst='C:/***/CoACD/build/_deps/boost-src'
  -- extracting... [tar xfz]
CUSTOMBUILD : CMake error : Problem with archive_write_header(): Invalid empty pathname [C:\***\CoACD\build\_deps\boost-subbuild\boost-populate.vcxproj]
  -- extracting... [error clean up]
CUSTOMBUILD : CMake error : Current file: [C:\***\CoACD\build\_deps\boost-subbuild\boost-populate.vcxproj]
CUSTOMBUILD : CMake error : Problem extracting tar: C:/***/CoACD/build/_deps/boost-subbuild/boost-populate-prefix/src/boost-1.81.0.tar.gz

.
.
.
CMake Error at C:/Program Files/CMake/share/cmake-3.31/Modules/FetchContent.cmake:1918 (message):
  Build step for boost failed: 1
Call Stack (most recent call first):
  C:/Program Files/CMake/share/cmake-3.31/Modules/FetchContent.cmake:1609 (__FetchContent_populateSubbuild)
  C:/Program Files/CMake/share/cmake-3.31/Modules/FetchContent.cmake:2145:EVAL:2 (__FetchContent_doPopulation)
  C:/Program Files/CMake/share/cmake-3.31/Modules/FetchContent.cmake:2145 (cmake_language)
  C:/Program Files/CMake/share/cmake-3.31/Modules/FetchContent.cmake:2384 (__FetchContent_Populate)
  cmake/boost.cmake:24 (FetchContent_MakeAvailable)
  CMakeLists.txt:38 (include)


-- Configuring incomplete, errors occurred!

Expected Behavior

The tar.gz archive should extract without issues.

Workaround

Switching to the zip archive of Boost resolves the problem:

FetchContent_Declare(
    boost
    URL https://github.com/boostorg/boost/releases/download/boost-1.81.0/boost-1.81.0.zip
    URL_HASH MD5=375693214b89309d2003f5296422c0a8
)
FetchContent_MakeAvailable(boost)

Environment

• Building for: Visual Studio 17 2022
• OS: Windows 11 Pro 23H2
• Windows SDK version 10.0.22621.0 to target Windows 10.0.22631.
• CMake Version: 3.31
• Compiler: MSVC 19.42.34435.0
• Boost Version: 1.81.0

Additional Notes

This issue seems specific to the tar.gz archive format on Windows. Similar setups on Linux and macOS work correctly with the same tar.gz archive. A potential solution could be to provide platform-specific recommendations for the archive format or improve the handling of tar archives in CMake.