Fix for Could not find PATCH using the following names: patch error on Windows MSVC

[alinaliBQ]

I started having build problems with error Could not find PATCH using the following names: patch after the commit e1f727c. I found it is because my system path doesn't have patch.exe on it. I wanted to share the fix that worked for me:

1. ensure you have git downloaded

2. check that patch.exe is inside C:\Program Files\Git\usr\bin on your machine

3. add C:\Program Files\Git\usr\bin to your PATH variable.

• I have added to both user and system PATH variable just to be safe

4. open terminal, run command patch --version and it should return successfully

5. rebuild arrow project, the build should succeed without the Could not find PATCH error

Build error:

101>-- Building (vendored) mimalloc from source
101>CMake Error at cmake_modules/ThirdpartyToolchain.cmake:2292 (find_program):
101>  Could not find PATCH using the following names: patch
101>Call Stack (most recent call first):
101>  CMakeLists.txt:523 (include)
101>
101>
101>-- Configuring incomplete, errors occurred!
101>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Microsoft\VC\v170\Microsoft.CppCommon.targets(254,5): error MSB8066: Custom build for 'C:\path\to\arrow\cpp\CMakeLists.txt' exited with code 1.
101>Done building project "ALL_BUILD.vcxproj" -- FAILED.

Code that gave the error if patch.exe is not on your system PATH variable:

arrow/cpp/cmake_modules/ThirdpartyToolchain.cmake

Line 2292 in 541cba8

find_program(PATCH patch REQUIRED)

[amoeba]

I think it wouldn't hurt to document this in the Windows dev docs (that git must be installed and in PATH). Feel free to open a PR.

[alinaliBQ]

Yea I am okay if anyone would like to open a PR using anything from my post. I am a bit busy with ODBC development at the moment

[amoeba]

Totally understand. Thanks for filing a discussion for this.

[amoeba]

I created #47839 to document this. Feel free to comment on that PR if you have any suggestions. I'm going to mark this Discussion as closed.