win32: support MinGW build

A MinGW build is the same shape as a MSVC build (but without
MzCOM), unlike a Cygwin build.

diff --git a/include/gc_config_macros.h b/include/gc_config_macros.h
index d2476b28bd00792f6ab760c620cdcea7ba7d7887..9c76e47204dad60545b55587226814b530228e3f 100644 (file)
--- a/include/gc_config_macros.h
+++ b/include/gc_config_macros.h
@@ -154,7 +154,7 @@
 #endif
 
 #if defined(__MINGW32__) && defined(GC_DLL)
-# ifdef GC_BUILD
+# if defined(GC_BUILD) || defined(__MINGW32_DELAY_LOAD__)
 #   define GC_API __declspec(dllexport)
 # else
 #   define GC_API __declspec(dllimport)