Merge pull request #11558 from DeterminateSystems/fix-no-gc-build

Fix build without GC

src/libexpr-c/nix_api_expr.cc

@@ -16,8 +16,6 @@
 
 #if HAVE_BOEHMGC
 #  include <mutex>
-#  define GC_INCLUDE_NEW 1
-#  include "gc_cpp.h"
 #endif
 
 nix_err nix_libexpr_init(nix_c_context * context)

src/libexpr/eval-gc.hh

@@ -23,7 +23,8 @@ template<typename T>
 using gc_allocator = std::allocator<T>;
 
 #  define GC_MALLOC_ATOMIC std::malloc
-#  define GC_STRDUP std::strdup
+#  define GC_STRDUP strdup
+
 struct gc
 {};