Micro-optimization handling Tcl_Panic(), suggested by D. Richard Hipp.

As a side-effect, this is as well a fix  for [1446864]: segfaults if Tcl_Panic() returns.

4 files changed, 26 insertions, 13 deletions

diff --git a/generic/tcl.decls b/generic/tcl.decls
index 1829249..a5cd24d 100644
--- a/generic/tcl.decls
+++ b/generic/tcl.decls
@@ -37,7 +37,7 @@ declare 1 {
 	    void *clientDataPtr)
 }
 declare 2 {
-    void Tcl_Panic(const char *format, ...)
+    TCL_NORETURN void Tcl_Panic(const char *format, ...)
 }
 declare 3 {
     char *Tcl_Alloc(unsigned int size)
@@ -815,7 +815,7 @@ declare 229 {
     void Tcl_SetMaxBlockTime(const Tcl_Time *timePtr)
 }
 declare 230 {
-    void Tcl_SetPanicProc(Tcl_PanicProc *panicProc)
+    void Tcl_SetPanicProc(TCL_NORETURN1 Tcl_PanicProc *panicProc)
 }
 declare 231 {
     int Tcl_SetRecursionLimit(Tcl_Interp *interp, int depth)
@@ -986,7 +986,7 @@ declare 277 {
     Tcl_Pid Tcl_WaitPid(Tcl_Pid pid, int *statPtr, int options)
 }
 declare 278 {
-    void Tcl_PanicVA(const char *format, va_list argList)
+    TCL_NORETURN void Tcl_PanicVA(const char *format, va_list argList)
 }
 declare 279 {
     void Tcl_GetVersion(int *major, int *minor, int *patchLevel, int *type)
diff --git a/generic/tcl.h b/generic/tcl.h
index 1f7b5cb..a08edde 100644
--- a/generic/tcl.h
+++ b/generic/tcl.h
@@ -143,8 +143,20 @@ extern "C" {
 #endif
 #if defined(__GNUC__) && (__GNUC__ > 2)
 #   define TCL_FORMAT_PRINTF(a,b) __attribute__ ((__format__ (__printf__, a, b)))
+#   define TCL_NORETURN __attribute__ ((noreturn))
+#   if defined(BUILD_tcl) || defined(BUILD_tk)
+#	define TCL_NORETURN1 __attribute__ ((noreturn))
+#   else
+#	define TCL_NORETURN1 /* nothing */
+#   endif
 #else
 #   define TCL_FORMAT_PRINTF(a,b)
+#   if defined(_MSC_VER) && (_MSC_VER >= 1310)
+#	define TCL_NORETURN _declspec(noreturn)
+#   else
+#	define TCL_NORETURN /* nothing */
+#   endif
+#   define TCL_NORETURN1 /* nothing */
 #endif
 
 /*
diff --git a/generic/tclDecls.h b/generic/tclDecls.h
index 91c0add..996129d 100644
--- a/generic/tclDecls.h
+++ b/generic/tclDecls.h
@@ -48,7 +48,7 @@ EXTERN CONST84_RETURN char * Tcl_PkgRequireEx(Tcl_Interp *interp,
 				const char *name, const char *version,
 				int exact, void *clientDataPtr);
 /* 2 */
-EXTERN void		Tcl_Panic(const char *format, ...) TCL_FORMAT_PRINTF(1, 2);
+EXTERN TCL_NORETURN void Tcl_Panic(const char *format, ...) TCL_FORMAT_PRINTF(1, 2);
 /* 3 */
 EXTERN char *		Tcl_Alloc(unsigned int size);
 /* 4 */
@@ -686,7 +686,8 @@ EXTERN void		Tcl_SetErrorCode(Tcl_Interp *interp, ...);
 /* 229 */
 EXTERN void		Tcl_SetMaxBlockTime(const Tcl_Time *timePtr);
 /* 230 */
-EXTERN void		Tcl_SetPanicProc(Tcl_PanicProc *panicProc);
+EXTERN void		Tcl_SetPanicProc(
+				TCL_NORETURN1 Tcl_PanicProc *panicProc);
 /* 231 */
 EXTERN int		Tcl_SetRecursionLimit(Tcl_Interp *interp, int depth);
 /* 232 */
@@ -835,7 +836,7 @@ EXTERN int		Tcl_VarEvalVA(Tcl_Interp *interp, va_list argList);
 /* 277 */
 EXTERN Tcl_Pid		Tcl_WaitPid(Tcl_Pid pid, int *statPtr, int options);
 /* 278 */
-EXTERN void		Tcl_PanicVA(const char *format, va_list argList);
+EXTERN TCL_NORETURN void Tcl_PanicVA(const char *format, va_list argList);
 /* 279 */
 EXTERN void		Tcl_GetVersion(int *major, int *minor,
 				int *patchLevel, int *type);
@@ -1828,7 +1829,7 @@ typedef struct TclStubs {
 
     int (*tcl_PkgProvideEx) (Tcl_Interp *interp, const char *name, const char *version, const void *clientData); /* 0 */
     CONST84_RETURN char * (*tcl_PkgRequireEx) (Tcl_Interp *interp, const char *name, const char *version, int exact, void *clientDataPtr); /* 1 */
-    void (*tcl_Panic) (const char *format, ...) TCL_FORMAT_PRINTF(1, 2); /* 2 */
+    TCL_NORETURN1 void (*tcl_Panic) (const char *format, ...) TCL_FORMAT_PRINTF(1, 2); /* 2 */
     char * (*tcl_Alloc) (unsigned int size); /* 3 */
     void (*tcl_Free) (char *ptr); /* 4 */
     char * (*tcl_Realloc) (char *ptr, unsigned int size); /* 5 */
@@ -2080,7 +2081,7 @@ typedef struct TclStubs {
     void (*tcl_SetErrno) (int err); /* 227 */
     void (*tcl_SetErrorCode) (Tcl_Interp *interp, ...); /* 228 */
     void (*tcl_SetMaxBlockTime) (const Tcl_Time *timePtr); /* 229 */
-    void (*tcl_SetPanicProc) (Tcl_PanicProc *panicProc); /* 230 */
+    void (*tcl_SetPanicProc) (TCL_NORETURN1 Tcl_PanicProc *panicProc); /* 230 */
     int (*tcl_SetRecursionLimit) (Tcl_Interp *interp, int depth); /* 231 */
     void (*tcl_SetResult) (Tcl_Interp *interp, char *result, Tcl_FreeProc *freeProc); /* 232 */
     int (*tcl_SetServiceMode) (int mode); /* 233 */
@@ -2128,7 +2129,7 @@ typedef struct TclStubs {
     void (*tcl_SetErrorCodeVA) (Tcl_Interp *interp, va_list argList); /* 275 */
     int (*tcl_VarEvalVA) (Tcl_Interp *interp, va_list argList); /* 276 */
     Tcl_Pid (*tcl_WaitPid) (Tcl_Pid pid, int *statPtr, int options); /* 277 */
-    void (*tcl_PanicVA) (const char *format, va_list argList); /* 278 */
+    TCL_NORETURN1 void (*tcl_PanicVA) (const char *format, va_list argList); /* 278 */
     void (*tcl_GetVersion) (int *major, int *minor, int *patchLevel, int *type); /* 279 */
     void (*tcl_InitMemory) (Tcl_Interp *interp); /* 280 */
     Tcl_Channel (*tcl_StackChannel) (Tcl_Interp *interp, const Tcl_ChannelType *typePtr, ClientData instanceData, int mask, Tcl_Channel prevChan); /* 281 */
diff --git a/generic/tclPanic.c b/generic/tclPanic.c
index 851695f..b032449 100644
--- a/generic/tclPanic.c
+++ b/generic/tclPanic.c
@@ -15,7 +15,7 @@
 
 #include "tclInt.h"
 #if defined(_WIN32) || defined(__CYGWIN__)
-    MODULE_SCOPE void tclWinDebugPanic(const char *format, ...);
+    MODULE_SCOPE TCL_NORETURN void tclWinDebugPanic(const char *format, ...);
 #endif
 
 /*
@@ -24,9 +24,9 @@
  */
 
 #if defined(__CYGWIN__)
-static Tcl_PanicProc *panicProc = tclWinDebugPanic;
+static TCL_NORETURN Tcl_PanicProc *panicProc = tclWinDebugPanic;
 #else
-static Tcl_PanicProc *panicProc = NULL;
+static TCL_NORETURN1 Tcl_PanicProc *panicProc = NULL;
 #endif
 
 /*
@@ -47,7 +47,7 @@ static Tcl_PanicProc *panicProc = NULL;
 
 void
 Tcl_SetPanicProc(
-    Tcl_PanicProc *proc)
+    TCL_NORETURN1 Tcl_PanicProc *proc)
 {
 #if defined(_WIN32)
     /* tclWinDebugPanic only installs if there is no panicProc yet. */