diff --git a/if1632/builtin.c b/if1632/builtin.c
index 0efda2de0e7..4e495c8f5e0 100644
--- a/if1632/builtin.c
+++ b/if1632/builtin.c
@@ -12,7 +12,6 @@
 #include "wine/winbase16.h"
 #include "wine/winestring.h"
 #include "builtin16.h"
-#include "builtin32.h"
 #include "global.h"
 #include "heap.h"
 #include "module.h"
diff --git a/include/builtin32.h b/include/builtin32.h
index fc42f48be78..7df211155d6 100644
--- a/include/builtin32.h
+++ b/include/builtin32.h
@@ -7,6 +7,7 @@
 #ifndef __WINE_BUILTIN32_H
 #define __WINE_BUILTIN32_H
 
+/* Warning: this must match the definition in tools/winebuild/spec32.c */
 typedef struct
 {
     const char*           filename;     /* DLL file name */
@@ -21,7 +22,6 @@ typedef struct
 } BUILTIN32_DESCRIPTOR;
 
 extern void BUILTIN32_RegisterDLL( const BUILTIN32_DESCRIPTOR *descr );
-extern void BUILTIN32_Unimplemented( const char *dllname, const char *funcname );
 extern void RELAY_SetupDLL( const char *module );
 
 #endif /* __WINE_BUILTIN32_H */
diff --git a/relay32/relay386.c b/relay32/relay386.c
index d764d86fb28..7da06f15d4a 100644
--- a/relay32/relay386.c
+++ b/relay32/relay386.c
@@ -9,7 +9,6 @@
 #include <string.h>
 #include <stdio.h>
 #include "winnt.h"
-#include "builtin32.h"
 #include "selectors.h"
 #include "stackframe.h"
 #include "syslevel.h"
diff --git a/relay32/snoop.c b/relay32/snoop.c
index d87ae070e3e..fbbb2d4272d 100644
--- a/relay32/snoop.c
+++ b/relay32/snoop.c
@@ -12,7 +12,6 @@
 #include "winbase.h"
 #include "winnt.h"
 #include "heap.h"
-#include "builtin32.h"
 #include "snoop.h"
 #include "neexe.h"
 #include "selectors.h"
diff --git a/tools/winebuild/spec32.c b/tools/winebuild/spec32.c
index 383cb0eb55b..e01d1749274 100644
--- a/tools/winebuild/spec32.c
+++ b/tools/winebuild/spec32.c
@@ -288,7 +288,7 @@ void BuildSpec32File( FILE *outfile )
 
     fprintf( outfile, "/* File generated automatically from %s; do not edit! */\n\n",
              input_file_name );
-    fprintf( outfile, "#include \"builtin32.h\"\n\n" );
+    fprintf( outfile, "extern void BUILTIN32_Unimplemented( const char *dllname, const char *funcname );\n\n" );
 
     /* Reserve some space for the PE header */
 
@@ -439,7 +439,18 @@ void BuildSpec32File( FILE *outfile )
 
     if (rsrc_name[0]) fprintf( outfile, "extern char %s[];\n\n", rsrc_name );
 
-    fprintf( outfile, "static const BUILTIN32_DESCRIPTOR descriptor =\n{\n" );
+    /* Warning: this must match the definition in builtin32.h */
+    fprintf( outfile, "static const struct dll_descriptor\n{\n" );
+    fprintf( outfile, "    const char*           filename;\n" );
+    fprintf( outfile, "    int                   nb_imports;\n" );
+    fprintf( outfile, "    void                 *pe_header;\n" );
+    fprintf( outfile, "    void                 *exports;\n" );
+    fprintf( outfile, "    unsigned int          exports_size;\n" );
+    fprintf( outfile, "    const char * const   *imports;\n" );
+    fprintf( outfile, "    void                (*dllentrypoint)();\n" );
+    fprintf( outfile, "    int                   characteristics;\n" );
+    fprintf( outfile, "    void                 *rsrc;\n" );
+    fprintf( outfile, "} descriptor = {\n" );
     fprintf( outfile, "    \"%s\",\n", DLLFileName );
     fprintf( outfile, "    %d,\n", nb_imports );
     fprintf( outfile, "    pe_header,\n" );
@@ -462,6 +473,7 @@ void BuildSpec32File( FILE *outfile )
     fprintf( outfile, "    \"\\t.previous\\n\");\n" );
     fprintf( outfile, "}\n" );
     fprintf( outfile, "#endif /* defined(__GNUC__) */\n" );
-    fprintf( outfile, "static void %s_init(void) { BUILTIN32_RegisterDLL( &descriptor ); }\n",
-             DLLName );
+    fprintf( outfile, "static void %s_init(void)\n{\n", DLLName );
+    fprintf( outfile, "    extern void BUILTIN32_RegisterDLL( const struct dll_descriptor * );\n" );
+    fprintf( outfile, "    BUILTIN32_RegisterDLL( &descriptor );\n}\n" );
 }