From 129f37050ea057fb02434df05badc3d8f96d6752 Mon Sep 17 00:00:00 2001
From: Ed Savage <ed.savage@elastic.co>
Date: Tue, 1 Sep 2026 09:12:02 +1200
Subject: [PATCH] Fail CMake configure if 3rd-party git clone fails (#3164)

Previously, execute_process() silently ignored a non-zero exit from the
git clone command. If the GitLab server is unavailable or overloaded,
CMake would continue configuring with no Eigen headers present, leading
to a cryptic compiler error hundreds of lines later instead of a clear
configure-time failure.

Same hardening for valijson as for pull-eigen.cmake: report a clear configure-time error
if the git clone fails rather than silently continuing and producing a
cryptic compiler error later.

(cherry picked from commit f95b8ef64348a8b5889b169e2ed77c696c497372)
---
 3rd_party/pull-eigen.cmake    | 4 ++++
 3rd_party/pull-valijson.cmake | 9 ++++++++-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/3rd_party/pull-eigen.cmake b/3rd_party/pull-eigen.cmake
index adcfc7a1bc..1a76f5a8c5 100644
--- a/3rd_party/pull-eigen.cmake
+++ b/3rd_party/pull-eigen.cmake
@@ -42,5 +42,9 @@ if(PULL_EIGEN)
   execute_process(
     COMMAND git -c advice.detachedHead=false clone --depth=1 --branch=3.4.0 https://gitlab.com/libeigen/eigen.git
     WORKING_DIRECTORY ${CMAKE_CURRENT_LIST_DIR}
+    RESULT_VARIABLE GIT_RESULT
     )
+  if(NOT GIT_RESULT EQUAL 0)
+    message(FATAL_ERROR "Failed to clone Eigen from https://gitlab.com/libeigen/eigen.git: git exited with ${GIT_RESULT}. Check network connectivity, proxy settings, and git availability.")
+  endif()
 endif()
diff --git a/3rd_party/pull-valijson.cmake b/3rd_party/pull-valijson.cmake
index 13f6e3e408..c80d4838d6 100644
--- a/3rd_party/pull-valijson.cmake
+++ b/3rd_party/pull-valijson.cmake
@@ -16,5 +16,12 @@
 # This cmake script is expected to be called from a target or custom command with WORKING_DIRECTORY set to this file's location
 
 if ( NOT EXISTS valijson )
-  execute_process( COMMAND git -c advice.detachedHead=false clone --depth=1 --branch=v1.0.2 https://github.com/tristanpenman/valijson.git WORKING_DIRECTORY ${CMAKE_CURRENT_LIST_DIR})
+  execute_process(
+    COMMAND git -c advice.detachedHead=false clone --depth=1 --branch=v1.0.2 https://github.com/tristanpenman/valijson.git
+    WORKING_DIRECTORY ${CMAKE_CURRENT_LIST_DIR}
+    RESULT_VARIABLE GIT_RESULT
+    )
+  if(NOT GIT_RESULT EQUAL 0)
+    message(FATAL_ERROR "Failed to clone Valijson from https://github.com/tristanpenman/valijson.git: git exited with ${GIT_RESULT}. Check network connectivity, proxy settings, and git availability.")
+  endif()
 endif()