diff --git a/Telegram/build/prepare/prepare.py b/Telegram/build/prepare/prepare.py
index 1b8a37c47c..86f88dc490 100644
--- a/Telegram/build/prepare/prepare.py
+++ b/Telegram/build/prepare/prepare.py
@@ -1077,6 +1077,7 @@ mac:
     cd openal-soft
     git checkout 716f5373cb
     CFLAGS=$UNGUARDED CPPFLAGS=$UNGUARDED cmake -B build . \\
+        -D CMAKE_BUILD_TYPE=RelWithDebInfo \\
         -D CMAKE_INSTALL_PREFIX:PATH=$USED_PREFIX \\
         -D ALSOFT_EXAMPLES=OFF \\
         -D ALSOFT_UTILS=OFF \\