merge trunk

Change the signature of TclInitStubs as agreed (hopefully).
Move the Tcl_InitStubs() function to a separate source file, so it will not be included when not needed.
Revert change in tcl.h, in stead define TclInitStubs in tclInt.h. For binary compatibility with older Tcl 8.6 versions.
No functional change in any way.

generic/tclInt.h

@@ -3859,6 +3859,8 @@ MODULE_SCOPE int	TclCompileStreqOpCmd(Tcl_Interp *interp,
 MODULE_SCOPE int	TclCompileAssembleCmd(Tcl_Interp *interp,
 			    Tcl_Parse *parsePtr, Command *cmdPtr,
 			    struct CompileEnv *envPtr);
+MODULE_SCOPE const char *TclInitStubs(Tcl_Interp *interp, const char *version,
+			    int exact, const char *tclversion, int magic);
 
 /*
  * Functions defined in generic/tclVar.c and currenttly exported only for use

generic/tclStubLib.c

@@ -34,11 +34,12 @@ const TclIntPlatStubs *tclIntPlatStubsPtr = NULL;
 
 static const TclStubs *
 HasStubSupport(
-    Tcl_Interp *interp)
+    Tcl_Interp *interp,
+    int magic)
 {
     Interp *iPtr = (Interp *) interp;
-
-    if (iPtr->stubTable && (iPtr->stubTable->magic == TCL_STUB_MAGIC)) {
+    if (iPtr->stubTable && iPtr->stubTable->magic == magic
+	    && iPtr->stubTable->magic == TCL_STUB_MAGIC) {
 	return iPtr->stubTable;
     }
     iPtr->result = (char *) "interpreter uses an incompatible stubs mechanism";
@@ -58,7 +59,7 @@ static int isDigit(const int c)
 /*
  *----------------------------------------------------------------------
  *
- * Tcl_InitStubs --
+ * TclInitStubs --
  *
  *	Tries to initialise the stub table pointers and ensures that the
  *	correct version of Tcl is loaded.
@@ -74,13 +75,19 @@ static int isDigit(const int c)
  */
 
 MODULE_SCOPE const char *
-Tcl_InitStubs(
+TclInitStubs(
     Tcl_Interp *interp,
     const char *version,
-    int exact)
+    int exact,
+    const char *tclversion,
+    int magic)
 {
+    const char *p;
+    char *q;
+    char major[TCL_INTEGER_SPACE];
     const char *actualVersion = NULL;
     ClientData pkgData = NULL;
+    Interp *iPtr = (Interp *) interp;
 
     /*
      * We can't optimize this check by caching tclStubsPtr because that
@@ -88,24 +95,51 @@ Tcl_InitStubs(
      * times. [Bug 615304]
      */
 
-    tclStubsPtr = HasStubSupport(interp);
+    tclStubsPtr = HasStubSupport(interp, magic);
     if (!tclStubsPtr) {
 	return NULL;
     }
 
+    /*
+     * Check that the [load]ing interp and [load]ed extension were compiled
+     * against headers from the same major version of Tcl.  If not, they
+     * will not agree on the layout of the stubs and will crash.  Report
+     * the error instead of crashing.
+     */
+
+    p = tclversion;
+    q = major;
+    while (isDigit(*p)) {
+	*q++ = *p++;
+	if (q-major > TCL_INTEGER_SPACE) {
+	    iPtr->result = (char *) "major version overflow";
+	    iPtr->freeProc = TCL_STATIC;
+	    return NULL;
+	}
+    }
+    *q = '\0';
+
+    if (NULL == Tcl_PkgRequireEx(interp, "Tcl", major, 0, NULL)) {
+	return NULL;
+    }
+
+    /*
+     * Check satisfaction of the requirement requested by the caller.
+     */
+
     actualVersion = Tcl_PkgRequireEx(interp, "Tcl", version, 0, &pkgData);
     if (actualVersion == NULL) {
 	return NULL;
     }
     if (exact) {
-	const char *p = version;
 	int count = 0;
 
+	p = version;
 	while (*p) {
 	    count += !isDigit(*p++);
 	}
 	if (count == 1) {
-	    const char *q = actualVersion;
+	    q = actualVersion;
 
 	    p = version;
 	    while (*p && (*p == *q)) {

generic/tclStubLibCompat.c

@@ -0,0 +1,57 @@
+/*
+ * tclStubLibCompat.c --
+ *
+ *	Stub object that will be statically linked into extensions that want
+ *	to access Tcl.
+ *
+ * Copyright (c) 2012 Jan Nijtmans
+ *
+ * See the file "license.terms" for information on usage and redistribution of
+ * this file, and for a DISCLAIMER OF ALL WARRANTIES.
+ */
+
+/*
+ * Small wrapper, which allows Tcl8 extensions to use the same stub
+ * library as Tcl 9.
+ */
+
+#include "tclInt.h"
+
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_InitStubs --
+ *
+ *	Tries to initialise the stub table pointers and ensures that the
+ *	correct version of Tcl is loaded.
+ *
+ * Results:
+ *	The actual version of Tcl that satisfies the request, or NULL to
+ *	indicate that an error occurred.
+ *
+ * Side effects:
+ *	Sets the stub table pointers.
+ *
+ *----------------------------------------------------------------------
+ */
+#undef Tcl_InitStubs
+
+MODULE_SCOPE const char *
+Tcl_InitStubs(
+    Tcl_Interp *interp,
+    const char *version,
+    int exact)
+{
+    /* Use the hardcoded TCL_VERSION and Tcl8 magic value here. */
+    return TclInitStubs(interp, version, exact, "8.6", (int) 0xFCA3BACF);
+}
+
+/*
+ * Local Variables:
+ * mode: c
+ * c-basic-offset: 4
+ * fill-column: 78
+ * End:
+ */
+

unix/Makefile.in

@@ -335,7 +335,7 @@ TOMMATH_OBJS = bncore.o bn_reverse.o bn_fast_s_mp_mul_digs.o \
 	bn_mp_unsigned_bin_size.o bn_mp_xor.o bn_mp_zero.o bn_s_mp_add.o \
         bn_s_mp_mul_digs.o bn_s_mp_sqr.o bn_s_mp_sub.o
 
-STUB_LIB_OBJS = tclStubLib.o tclTomMathStubLib.o tclOOStubLib.o ${COMPAT_OBJS}
+STUB_LIB_OBJS = tclStubLib.o tclStubLibCompat.o tclTomMathStubLib.o tclOOStubLib.o ${COMPAT_OBJS}
 
 UNIX_OBJS = tclUnixChan.o tclUnixEvent.o tclUnixFCmd.o \
 	tclUnixFile.o tclUnixPipe.o tclUnixSock.o \
@@ -468,6 +468,7 @@ OO_SRCS = \
 
 STUB_SRCS = \
 	$(GENERIC_DIR)/tclStubLib.c \
+	$(GENERIC_DIR)/tclStubCompat.c \
 	$(GENERIC_DIR)/tclTomMathStubLib.c \
 	$(GENERIC_DIR)/tclOOStubLib.c
 
@@ -1656,6 +1657,9 @@ Zzutil.o:    $(ZLIB_DIR)/zutil.c
 tclStubLib.o: $(GENERIC_DIR)/tclStubLib.c
 	$(CC) -c $(STUB_CC_SWITCHES) $(GENERIC_DIR)/tclStubLib.c
 
+tclStubLibCompat.o: $(GENERIC_DIR)/tclStubLibCompat.c
+	$(CC) -c $(STUB_CC_SWITCHES) $(GENERIC_DIR)/tclStubLibCompat.c
+
 tclTomMathStubLib.o: $(GENERIC_DIR)/tclTomMathStubLib.c
 	$(CC) -c $(STUB_CC_SWITCHES) $(GENERIC_DIR)/tclTomMathStubLib.c
 

win/Makefile.in

@@ -378,6 +378,7 @@ REG_OBJS = tclWinReg.$(OBJEXT)
 
 STUB_OBJS = \
 	tclStubLib.$(OBJEXT) \
+	tclStubLibCompat.$(OBJEXT) \
 	tclTomMathStubLib.$(OBJEXT) \
 	tclOOStubLib.$(OBJEXT)
 
@@ -508,6 +509,9 @@ tclPkgConfig.${OBJEXT}: tclPkgConfig.c
 tclStubLib.${OBJEXT}: tclStubLib.c
 	$(CC) -c $(CC_SWITCHES) -DSTATIC_BUILD @DEPARG@ $(CC_OBJNAME)
 
+tclStubLibCompat.${OBJEXT}: tclStubLibCompat.c
+	$(CC) -c $(CC_SWITCHES) -DSTATIC_BUILD @DEPARG@ $(CC_OBJNAME)
+
 tclTomMathStubLib.${OBJEXT}: tclTomMathStubLib.c
 	$(CC) -c $(CC_SWITCHES) -DSTATIC_BUILD @DEPARG@ $(CC_OBJNAME)
 

win/makefile.vc

@@ -448,6 +448,7 @@ TCLOBJS = $(COREOBJS) $(ZLIBOBJS) $(TOMMATHOBJS) $(PLATFORMOBJS)
 
 TCLSTUBOBJS = \
 	$(TMP_DIR)\tclStubLib.obj \
+	$(TMP_DIR)\tclStubLibCompat.obj \
 	$(TMP_DIR)\tclTomMathStubLib.obj \
 	$(TMP_DIR)\tclOOStubLib.obj
 
@@ -977,6 +978,9 @@ $(TMP_DIR)\tclWinDde.obj: $(WINDIR)\tclWinDde.c
 $(TMP_DIR)\tclStubLib.obj: $(GENERICDIR)\tclStubLib.c
 	$(cc32) $(STUB_CFLAGS) -Zl -DSTATIC_BUILD $(TCL_INCLUDES) -Fo$@ $?
 
+$(TMP_DIR)\tclStubLibCompat.obj: $(GENERICDIR)\tclStubLibCompat.c
+	$(cc32) $(STUB_CFLAGS) -Zl -DSTATIC_BUILD $(TCL_INCLUDES) -Fo$@ $?
+
 $(TMP_DIR)\tclTomMathStubLib.obj: $(GENERICDIR)\tclTomMathStubLib.c
 	$(cc32) $(STUB_CFLAGS) -Zl -DSTATIC_BUILD $(TCL_INCLUDES) -Fo$@ $?