diff --git a/CHANGELOG b/CHANGELOG
index f6795b93..ea94f1ad 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -32,7 +32,7 @@
 ** Enhancements
 - less cryptic names in backtraces of C-compiled functions
 - ECL can now use precompiled headers to speed up compilation. Use ~(setq
-  c::*use-precompiled-headers* nil)~ to disable this feature
+  c::*use-precompiled-headers* t)~ to enable this feature
 ** Issues fixed
 - the generational and precise garbage collector modes work again
 - ~serve-event~ extension may be used simultaneously from different threads now
diff --git a/src/cmp/cmpglobals.lsp b/src/cmp/cmpglobals.lsp
index 36bcaa56..04040f12 100644
--- a/src/cmp/cmpglobals.lsp
+++ b/src/cmp/cmpglobals.lsp
@@ -212,7 +212,7 @@ slashes before special characters.")
 and standalone programs. It is not required to surround values with quotes or use
 slashes before special characters.")
 
-(defvar *use-precompiled-headers* #+msvc nil #-msvc t
+(defvar *use-precompiled-headers* nil
 "This variable controls whether the C compiler uses precompiled header files.")
 (defvar *precompiled-header-flags* nil)
 (defvar *precompiled-header-cc-config* nil)