[clang] 0ce76c7 - [clang-format] Don't check the format if diff is unavailable (#205036)

[via cfe-commits]

Author: owenca
Date: 2026-06-23T08:17:12-07:00
New Revision: 0ce76c77c9e0ee15905d76500bfa0235c2ac3741

URL: https://github.com/llvm/llvm-project/commit/0ce76c77c9e0ee15905d76500bfa0235c2ac3741
DIFF: https://github.com/llvm/llvm-project/commit/0ce76c77c9e0ee15905d76500bfa0235c2ac3741.diff

LOG: [clang-format] Don't check the format if diff is unavailable (#205036)

Added: 
    

Modified: 
    clang/lib/Format/CMakeLists.txt

Removed: 
    


################################################################################
diff  --git a/clang/lib/Format/CMakeLists.txt b/clang/lib/Format/CMakeLists.txt
index 3e19151790440..df73212983ab1 100644
--- a/clang/lib/Format/CMakeLists.txt
+++ b/clang/lib/Format/CMakeLists.txt
@@ -41,21 +41,27 @@ file(GLOB_RECURSE files
   ${CLANG_SOURCE_DIR}/unittests/Format/*.h
   )
 
-set(check_format_depends)
-set(i 0)
-foreach(file IN LISTS files)
-  add_custom_command(OUTPUT check_format_depend_${i}
-    COMMAND clang-format ${file} | 
diff  -u ${file} - &&
-            touch check_format_depend_${i}
-    VERBATIM
-    COMMENT "Checking format of ${file}"
-    DEPENDS clang-format
-            ${file}
-    )
-  list(APPEND check_format_depends check_format_depend_${i})
-  math(EXPR i ${i}+1)
-endforeach()
-add_custom_target(clang-format-check-format DEPENDS ${check_format_depends})
+find_program(DIFF_EXE 
diff )
+if(DIFF_EXE)
+  set(check_format_depends)
+  set(i 0)
+  foreach(file IN LISTS files)
+    add_custom_command(OUTPUT check_format_depend_${i}
+      COMMAND clang-format ${file} | 
diff  -u ${file} - &&
+              touch check_format_depend_${i}
+      VERBATIM
+      COMMENT "Checking format of ${file}"
+      DEPENDS clang-format
+              ${file}
+      )
+    list(APPEND check_format_depends check_format_depend_${i})
+    math(EXPR i ${i}+1)
+  endforeach()
+  add_custom_target(clang-format-check-format DEPENDS ${check_format_depends})
+else()
+  add_custom_target(clang-format-check-format DEPENDS clang-format)
+endif()
+
 
 set(docs_tools_dir ${CLANG_SOURCE_DIR}/docs/tools)