[C++] Building Arrow via FetchContent can fail with versions older than CMake 3.30

Describe the bug, including details regarding any error messages, version, and platform.

As seen on the iceberg-cpp report here:

build: regression after #1021 — Arrow's arrow_SOURCE_DIR collides with FetchContent on CMake 3.28, breaks vendored Arrow build iceberg-cpp#1028

Building Arrow via FetchContent on iceberg with older CMake fails. This is because:

For older versions of CMake the variable arrow_SOURCE_DIR is overriden by FetchContent's one because project(arrow) sets it as a cache variable while FetchContent sets a normal variable with precedence. Arrow can't find thirdparty/versions.txt because it is pointing to the tarball root instead of the cpp subfolder. See policy https://cmake.org/cmake/help/latest/policy/CMP0180.html
We should fix upstream Arrow so it does not rely on arrow_SOURCE_DIR to allow older CMake builds.

See the PR I did here with the patch:

build: apply patch on Arrow so it can be used with older versions of CMake iceberg-cpp#1029

Component(s)

C++

@kou

@kou what do you think about this, the patch I apply there seems to fix the issues:

--- a/cpp/cmake_modules/ThirdpartyToolchain.cmake
+++ b/cpp/cmake_modules/ThirdpartyToolchain.cmake
@@ -365,7 +365,7 @@
 # ----------------------------------------------------------------------
 # Thirdparty versions, environment variables, source URLs

-set(THIRDPARTY_DIR "${arrow_SOURCE_DIR}/thirdparty")
+set(THIRDPARTY_DIR "${ARROW_SOURCE_DIR}/thirdparty")

 add_library(arrow::flatbuffers INTERFACE IMPORTED)
 target_include_directories(arrow::flatbuffers

+1

Let's apply the change in apache/arrow too.

GH-53995: [C++] Fix building Arrow via FetchContent with older versio…

Issue resolved by pull request 54573
#54573

Navigation Menu

Repository navigation

[C++] Building Arrow via FetchContent can fail with versions older than CMake 3.30 #53995

Describe the bug, including details regarding any error messages, version, and platform.

Component(s)

Metadata

Assignees

Labels

Type

Projects

Milestone

Relationships

Development

[C++] Building Arrow via FetchContent can fail with versions older than CMake 3.30 #53995

Description

Describe the bug, including details regarding any error messages, version, and platform.

Component(s)

Activity

raulcd commented on Oct 16, 2026

kou commented on Oct 16, 2026

kou commented on Oct 29, 2026

Metadata

Metadata

Assignees

Labels

Type

Projects

Milestone

Relationships

Development

Issue actions