From d506b8a5ed6d499129ed6f3e4e453ab3f70e9795 Mon Sep 17 00:00:00 2001
From: Sebastian Ullrich <sebasti@nullri.ch>
Date: Fri, 17 Sep 2021 17:51:49 +0200
Subject: [PATCH] feat: hide non-exported symbols on Unix

---
 src/CMakeLists.txt      | 3 +++
 src/include/lean/lean.h | 2 +-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index e84126ad8f..6391982b27 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -308,6 +308,9 @@ endif()
 if(NOT(${CMAKE_SYSTEM_NAME} MATCHES "Windows"))
   # export symbols for the interpreter (done via `LEAN_EXPORT` for Windows)
   set(LEAN_DYN_EXE_LINKER_FLAGS "${LEAN_DYN_EXE_LINKER_FLAGS} -rdynamic")
+  # hide all other symbols
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fvisibility=hidden -fvisibility-inlines-hidden")
+  set(LEANC_EXTRA_FLAGS "${LEANC_EXTRA_FLAGS} -fvisibility=hidden -fvisibility-inlines-hidden")
 endif()
 
 # On Windows, add bcrypt for random number generation
diff --git a/src/include/lean/lean.h b/src/include/lean/lean.h
index cc76e4791f..081726de6c 100644
--- a/src/include/lean/lean.h
+++ b/src/include/lean/lean.h
@@ -49,7 +49,7 @@ extern "C" {
 #ifdef _WIN32
 #define LEAN_EXPORT __declspec(dllexport)
 #else
-#define LEAN_EXPORT
+#define LEAN_EXPORT __attribute__((visibility("default")))
 #endif
 
 // We set `LEAN_EXPORTING` when compiling objects of libleanshared, but not when including this header in any other context.