X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=perlio.c;h=288159c188c2ff7de17afd7a0a6e864c99d12470;hb=5f2d99664d8a6923d24892ffc0569f4e03e22edd;hp=30a40cb53b3f4adfcbe23356676b7f97ae651189;hpb=f4ae5be69aab22df54900ebee32a57ed082c7017;p=p5sagit%2Fp5-mst-13.2.git

diff --git a/perlio.c b/perlio.c
index 30a40cb..288159c 100644
--- a/perlio.c
+++ b/perlio.c
@@ -30,7 +30,11 @@
 #ifdef PERL_MICRO
 #   include "uconfig.h"
 #else
-#   include "config.h"
+#   ifndef USE_CROSS_COMPILE
+#       include "config.h"
+#   else
+#       include "xconfig.h"
+#   endif
 #endif
 
 #define PERLIO_NOT_STDIO 0
@@ -358,6 +362,7 @@ Perl_boot_core_PerlIO(pTHX)
 void
 PerlIO_init(pTHX)
 {
+    PERL_UNUSED_CONTEXT;
     /*
      * Does nothing (yet) except force this file to be included in perl
      * binary. That allows this file to force inclusion of other functions
@@ -395,6 +400,7 @@ PerlIO_tmpfile(void)
 void
 PerlIO_init(pTHX)
 {
+    PERL_UNUSED_CONTEXT;
     /*
      * Force this file to be included in perl binary. Which allows this
      * file to force inclusion of other functions that may be required by
@@ -473,7 +479,11 @@ PerlIO_debug(const char *fmt, ...)
 	/* Use fixed buffer as sv_catpvf etc. needs SVs */
 	char buffer[1024];
 	const STRLEN len = my_sprintf(buffer, "%.40s:%" IVdf " ", s ? s : "(none)", (IV) CopLINE(PL_curcop));
+# ifdef USE_VSNPRINTF
+	const STRLEN len2 = vsnprintf(buffer+len, sizeof(buffer) - len, fmt, ap);
+# else
 	const STRLEN len2 = vsprintf(buffer+len, fmt, ap);
+# endif /* USE_VSNPRINTF */
 	PerlLIO_write(PL_perlio_debug_fd, buffer, len + len2);
 #else
 	const char *s = CopFILE(PL_curcop);
@@ -571,6 +581,7 @@ PerlIO_list_t *
 PerlIO_list_alloc(pTHX)
 {
     PerlIO_list_t *list;
+    PERL_UNUSED_CONTEXT;
     Newxz(list, 1, PerlIO_list_t);
     list->refcnt = 1;
     return list;
@@ -599,6 +610,8 @@ PerlIO_list_push(pTHX_ PerlIO_list_t *list, PerlIO_funcs *funcs, SV *arg)
 {
     dVAR;
     PerlIO_pair_t *p;
+    PERL_UNUSED_CONTEXT;
+
     if (list->cur >= list->len) {
 	list->len += 8;
 	if (list->array)
@@ -609,14 +622,14 @@ PerlIO_list_push(pTHX_ PerlIO_list_t *list, PerlIO_funcs *funcs, SV *arg)
     p = &(list->array[list->cur++]);
     p->funcs = funcs;
     if ((p->arg = arg)) {
-	(void)SvREFCNT_inc(arg);
+	SvREFCNT_inc_simple_void_NN(arg);
     }
 }
 
 PerlIO_list_t *
 PerlIO_clone_list(pTHX_ PerlIO_list_t *proto, CLONE_PARAMS *param)
 {
-    PerlIO_list_t *list = (PerlIO_list_t *) NULL;
+    PerlIO_list_t *list = NULL;
     if (proto) {
 	int i;
 	list = PerlIO_list_alloc(aTHX);
@@ -640,7 +653,7 @@ PerlIO_clone(pTHX_ PerlInterpreter *proto, CLONE_PARAMS *param)
     PL_known_layers = PerlIO_clone_list(aTHX_ proto->Iknown_layers, param);
     PL_def_layerlist = PerlIO_clone_list(aTHX_ proto->Idef_layerlist, param);
     PerlIO_allocate(aTHX); /* root slot is never used */
-    PerlIO_debug("Clone %p from %p\n",aTHX,proto);
+    PerlIO_debug("Clone %p from %p\n",(void*)aTHX,(void*)proto);
     while ((f = *table)) {
 	    int i;
 	    table = (PerlIO **) (f++);
@@ -652,6 +665,7 @@ PerlIO_clone(pTHX_ PerlInterpreter *proto, CLONE_PARAMS *param)
 	    }
 	}
 #else
+    PERL_UNUSED_CONTEXT;
     PERL_UNUSED_ARG(proto);
     PERL_UNUSED_ARG(param);
 #endif
@@ -664,7 +678,7 @@ PerlIO_destruct(pTHX)
     PerlIO **table = &PL_perlio;
     PerlIO *f;
 #ifdef USE_ITHREADS
-    PerlIO_debug("Destruct %p\n",aTHX);
+    PerlIO_debug("Destruct %p\n",(void*)aTHX);
 #endif
     while ((f = *table)) {
 	int i;
@@ -769,8 +783,7 @@ PerlIO_find_layer(pTHX_ const char *name, STRLEN len, int load)
 	    SAVEINT(PL_in_load_module);
 	    if (cv) {
 		SAVEGENERICSV(PL_warnhook);
-		(void)SvREFCNT_inc(cv);
-		PL_warnhook = (SV *) cv;
+		PL_warnhook = (SV *) (SvREFCNT_inc_simple_NN(cv));
 	    }
 	    PL_in_load_module++;
 	    /*
@@ -853,7 +866,7 @@ XS(XS_io_MODIFY_SCALAR_ATTRIBUTES)
 	const char * const name = SvPV_const(ST(i), len);
 	SV * const layer = PerlIO_find_layer(aTHX_ name, len, 1);
 	if (layer) {
-	    av_push(av, SvREFCNT_inc(layer));
+	    av_push(av, SvREFCNT_inc_simple_NN(layer));
 	}
 	else {
 	    ST(count) = ST(i);
@@ -1178,19 +1191,26 @@ PerlIO_push(pTHX_ PerlIO *f, PERLIO_FUNCS_DECL(*tab), const char *mode, SV *arg)
 	    goto mismatch;
 	}
 	/* Real layer with a data area */
-	Newxc(l,tab->size,char,PerlIOl);
-	if (l && f) {
-	    Zero(l, tab->size, char);
-	    l->next = *f;
-	    l->tab = (PerlIO_funcs*) tab;
-	    *f = l;
-	    PerlIO_debug("PerlIO_push f=%p %s %s %p\n", (void*)f, tab->name,
-			(mode) ? mode : "(Null)", (void*)arg);
-	    if (*l->tab->Pushed &&
-		(*l->tab->Pushed) (aTHX_ f, mode, arg, (PerlIO_funcs*) tab) != 0) {
-		PerlIO_pop(aTHX_ f);
-		return NULL;
+	if (f) {
+	    char *temp;
+	    Newxz(temp, tab->size, char);
+	    l = (PerlIOl*)temp;
+	    if (l) {
+		l->next = *f;
+		l->tab = (PerlIO_funcs*) tab;
+		*f = l;
+		PerlIO_debug("PerlIO_push f=%p %s %s %p\n",
+			     (void*)f, tab->name,
+			     (mode) ? mode : "(Null)", (void*)arg);
+		if (*l->tab->Pushed &&
+		    (*l->tab->Pushed)
+		      (aTHX_ f, mode, arg, (PerlIO_funcs*) tab) != 0) {
+		    PerlIO_pop(aTHX_ f);
+		    return NULL;
+		}
 	    }
+	    else
+		return NULL;
 	}
     }
     else if (f) {
@@ -1494,7 +1514,7 @@ PerlIO_resolve_layers(pTHX_ const char *layers,
 	}
 	else {
 	    PerlIO_list_free(aTHX_ av);
-	    return (PerlIO_list_t *) NULL;
+	    return NULL;
 	}
     }
     else {
@@ -1833,6 +1853,7 @@ Perl_PerlIO_set_ptrcnt(pTHX_ PerlIO *f, STDCHAR * ptr, int cnt)
 IV
 PerlIOUtf8_pushed(pTHX_ PerlIO *f, const char *mode, SV *arg, PerlIO_funcs *tab)
 {
+    PERL_UNUSED_CONTEXT;
     PERL_UNUSED_ARG(mode);
     PERL_UNUSED_ARG(arg);
     if (PerlIOValid(f)) {
@@ -2000,6 +2021,7 @@ IV
 PerlIOBase_pushed(pTHX_ PerlIO *f, const char *mode, SV *arg, PerlIO_funcs *tab)
 {
     PerlIOl * const l = PerlIOBase(f);
+    PERL_UNUSED_CONTEXT;
     PERL_UNUSED_ARG(arg);
 
     l->flags &= ~(PERLIO_F_CANREAD | PERLIO_F_CANWRITE |
@@ -2058,6 +2080,7 @@ PerlIOBase_pushed(pTHX_ PerlIO *f, const char *mode, SV *arg, PerlIO_funcs *tab)
 IV
 PerlIOBase_popped(pTHX_ PerlIO *f)
 {
+    PERL_UNUSED_CONTEXT;
     PERL_UNUSED_ARG(f);
     return 0;
 }
@@ -2090,7 +2113,7 @@ PerlIOBase_read(pTHX_ PerlIO *f, void *vbuf, Size_t count)
 	    SSize_t avail = PerlIO_get_cnt(f);
 	    SSize_t take = 0;
 	    if (avail > 0)
-		take = ((SSize_t)count < avail) ? count : avail;
+		take = ((SSize_t)count < avail) ? (SSize_t)count : avail;
 	    if (take > 0) {
 		STDCHAR *ptr = PerlIO_get_ptr(f);
 		Copy(ptr, buf, take, STDCHAR);
@@ -2114,6 +2137,7 @@ PerlIOBase_read(pTHX_ PerlIO *f, void *vbuf, Size_t count)
 IV
 PerlIOBase_noop_ok(pTHX_ PerlIO *f)
 {
+    PERL_UNUSED_CONTEXT;
     PERL_UNUSED_ARG(f);
     return 0;
 }
@@ -2121,6 +2145,7 @@ PerlIOBase_noop_ok(pTHX_ PerlIO *f)
 IV
 PerlIOBase_noop_fail(pTHX_ PerlIO *f)
 {
+    PERL_UNUSED_CONTEXT;
     PERL_UNUSED_ARG(f);
     return -1;
 }
@@ -2157,6 +2182,7 @@ PerlIOBase_close(pTHX_ PerlIO *f)
 IV
 PerlIOBase_eof(pTHX_ PerlIO *f)
 {
+    PERL_UNUSED_CONTEXT;
     if (PerlIOValid(f)) {
 	return (PerlIOBase(f)->flags & PERLIO_F_EOF) != 0;
     }
@@ -2166,6 +2192,7 @@ PerlIOBase_eof(pTHX_ PerlIO *f)
 IV
 PerlIOBase_error(pTHX_ PerlIO *f)
 {
+    PERL_UNUSED_CONTEXT;
     if (PerlIOValid(f)) {
 	return (PerlIOBase(f)->flags & PERLIO_F_ERROR) != 0;
     }
@@ -2186,6 +2213,7 @@ PerlIOBase_clearerr(pTHX_ PerlIO *f)
 void
 PerlIOBase_setlinebuf(pTHX_ PerlIO *f)
 {
+    PERL_UNUSED_CONTEXT;
     if (PerlIOValid(f)) {
 	PerlIOBase(f)->flags |= PERLIO_F_LINEBUF;
     }
@@ -2248,6 +2276,7 @@ perl_mutex PerlIO_mutex;
 /* Must be called with PerlIO_mutex locked.  */
 static void
 S_more_refcounted_fds(pTHX_ const int new_fd) {
+    dVAR;
     const int old_max = PL_perlio_fd_refcnt_size;
     const int new_max = 16 + (new_fd & ~15);
     int *new_array;
@@ -2277,7 +2306,9 @@ S_more_refcounted_fds(pTHX_ const int new_fd) {
     PL_perlio_fd_refcnt_size = new_max;
     PL_perlio_fd_refcnt = new_array;
 
-    PerlIO_debug("Zeroing %p, %d\n", new_array + old_max, new_max - old_max);
+    PerlIO_debug("Zeroing %p, %d\n",
+		 (void*)(new_array + old_max),
+		 new_max - old_max);
 
     Zero(new_array + old_max, new_max - old_max, int);
 }
@@ -2289,6 +2320,8 @@ PerlIO_init(pTHX)
  /* Place holder for stdstreams call ??? */
 #ifdef USE_THREADS
     MUTEX_INIT(&PerlIO_mutex);
+#else
+    PERL_UNUSED_CONTEXT;
 #endif
 }
 
@@ -2344,7 +2377,7 @@ PerlIO_cleanup(pTHX)
     dVAR;
     int i;
 #ifdef USE_ITHREADS
-    PerlIO_debug("Cleanup layers for %p\n",aTHX);
+    PerlIO_debug("Cleanup layers for %p\n",(void*)aTHX);
 #else
     PerlIO_debug("Cleanup layers\n");
 #endif
@@ -2438,6 +2471,7 @@ PerlIOUnix_oflags(const char *mode)
 IV
 PerlIOUnix_fileno(pTHX_ PerlIO *f)
 {
+    PERL_UNUSED_CONTEXT;
     return PerlIOSelf(f, PerlIOUnix)->fd;
 }
 
@@ -2460,6 +2494,7 @@ PerlIOUnix_setfd(pTHX_ PerlIO *f, int fd, int imode)
     s->fd = fd;
     s->oflags = imode;
     PerlIOUnix_refcnt_inc(fd);
+    PERL_UNUSED_CONTEXT;
 }
 
 IV
@@ -2487,6 +2522,7 @@ PerlIOUnix_seek(pTHX_ PerlIO *f, Off_t offset, int whence)
 {
     const int fd = PerlIOSelf(f, PerlIOUnix)->fd;
     Off_t new_loc;
+    PERL_UNUSED_CONTEXT;
     if (PerlIOBase(f)->flags & PERLIO_F_NOTREG) {
 #ifdef  ESPIPE
 	SETERRNO(ESPIPE, LIB_INVARG);
@@ -2542,6 +2578,7 @@ PerlIOUnix_open(pTHX_ PerlIO_funcs *self, PerlIO_list_t *layers,
     }
     else {
 	if (f) {
+	    NOOP;
 	    /*
 	     * FIXME: pop layers ???
 	     */
@@ -2629,6 +2666,8 @@ PerlIOUnix_write(pTHX_ PerlIO *f, const void *vbuf, Size_t count)
 Off_t
 PerlIOUnix_tell(pTHX_ PerlIO *f)
 {
+    PERL_UNUSED_CONTEXT;
+
     return PerlLIO_lseek(PerlIOSelf(f, PerlIOUnix)->fd, 0, SEEK_CUR);
 }
 
@@ -2714,6 +2753,8 @@ typedef struct {
 IV
 PerlIOStdio_fileno(pTHX_ PerlIO *f)
 {
+    PERL_UNUSED_CONTEXT;
+
     if (PerlIOValid(f)) {
 	FILE * const s = PerlIOSelf(f, PerlIOStdio)->stdio;
 	if (s)
@@ -2842,7 +2883,6 @@ PerlIOStdio_open(pTHX_ PerlIO_funcs *self, PerlIO_list_t *layers,
 #endif
 		stdio = PerlSIO_fopen(path, mode);
 		if (stdio) {
-		    PerlIOStdio *s;
 		    if (!f) {
 			f = PerlIO_allocate(aTHX);
 		    }
@@ -2850,9 +2890,10 @@ PerlIOStdio_open(pTHX_ PerlIO_funcs *self, PerlIO_list_t *layers,
 		        mode = PerlIOStdio_mode(mode, tmode);
 		    f = PerlIO_push(aTHX_ f, self, mode, PerlIOArg);
 		    if (f) {
-			s = PerlIOSelf(f, PerlIOStdio);
-			s->stdio = stdio;
-			PerlIOUnix_refcnt_inc(fileno(s->stdio));
+			PerlIOSelf(f, PerlIOStdio)->stdio = stdio;
+			PerlIOUnix_refcnt_inc(fileno(stdio));
+		    } else {
+			PerlSIO_fclose(stdio);
 		    }
 		    return f;
 		}
@@ -2890,9 +2931,8 @@ PerlIOStdio_open(pTHX_ PerlIO_funcs *self, PerlIO_list_t *layers,
 		    f = PerlIO_allocate(aTHX);
 		}
 		if ((f = PerlIO_push(aTHX_ f, self, mode, PerlIOArg))) {
-		    PerlIOStdio * const s = PerlIOSelf(f, PerlIOStdio);
-		    s->stdio = stdio;
-		    PerlIOUnix_refcnt_inc(fileno(s->stdio));
+		    PerlIOSelf(f, PerlIOStdio)->stdio = stdio;
+		    PerlIOUnix_refcnt_inc(fileno(stdio));
 		}
 		return f;
 	    }
@@ -2918,6 +2958,7 @@ PerlIOStdio_dup(pTHX_ PerlIO *f, PerlIO *o, CLONE_PARAMS *param, int flags)
 		goto set_this;
 	    }
 	    else {
+		NOOP;
 		/* FIXME: To avoid messy error recovery if dup fails
 		   re-use the existing stdio as though flag was not set
 		 */
@@ -2934,6 +2975,8 @@ PerlIOStdio_dup(pTHX_ PerlIO *f, PerlIO *o, CLONE_PARAMS *param, int flags)
 static int
 PerlIOStdio_invalidate_fileno(pTHX_ FILE *f)
 {
+    PERL_UNUSED_CONTEXT;
+
     /* XXX this could use PerlIO_canset_fileno() and
      * PerlIO_set_fileno() support from Configure
      */
@@ -2948,31 +2991,7 @@ PerlIOStdio_invalidate_fileno(pTHX_ FILE *f)
     f->_fileno = -1;
     return 1;
 #  elif defined(__sun__)
-#    if defined(_LP64)
-    /* On solaris, if _LP64 is defined, the FILE structure is this:
-     *
-     *  struct FILE {
-     *      long __pad[16];
-     *  };
-     *
-     * It turns out that the fd is stored in the top 32 bits of
-     * file->__pad[4]. The lower 32 bits contain flags. file->pad[5] appears
-     * to contain a pointer or offset into another structure. All the
-     * remaining fields are zero.
-     *
-     * We set the top bits to -1 (0xFFFFFFFF).
-     */
-    f->__pad[4] |= 0xffffffff00000000L;
-    assert(fileno(f) == 0xffffffff);
-#    else /* !defined(_LP64) */
-    /* _file is just a unsigned char :-(
-       Not clear why we dup() rather than using -1
-       even if that would be treated as 0xFF - so will
-       a dup fail ...
-     */
-    f->_file = PerlLIO_dup(fileno(f));
-#    endif /* defined(_LP64) */
-    return 1;
+    return 0;
 #  elif defined(__hpux)
     f->__fileH = 0xff;
     f->__fileL = 0xff;
@@ -3043,7 +3062,6 @@ PerlIOStdio_close(pTHX_ PerlIO *f)
     }
     else {
         const int fd = fileno(stdio);
-	int socksfd = 0;
 	int invalidate = 0;
 	IV result = 0;
 	int saveerr = 0;
@@ -3055,36 +3073,26 @@ PerlIOStdio_close(pTHX_ PerlIO *f)
 	 */
     	int optval;
     	Sock_size_t optlen = sizeof(int);
-    	if (getsockopt(fd, SOL_SOCKET, SO_TYPE, (void *) &optval, &optlen) == 0) {
-            socksfd = 1;
+	if (getsockopt(fd, SOL_SOCKET, SO_TYPE, (void *) &optval, &optlen) == 0)
 	    invalidate = 1;
-    	}
 #endif
-    	if (PerlIOUnix_refcnt_dec(fd) > 0) {
-	    /* File descriptor still in use */
+	if (PerlIOUnix_refcnt_dec(fd) > 0) /* File descriptor still in use */
 	    invalidate = 1;
-	    socksfd = 0;
-	}
 	if (invalidate) {
-   	    /* For STD* handles don't close the stdio at all
-	       this is because we have shared the FILE * too
-   	     */
-	    if (stdio == stdin) {
-	    	/* Some stdios are buggy fflush-ing inputs */
-	    	return 0;
-	    }
-	    else if (stdio == stdout || stdio == stderr) {
-	    	return PerlIO_flush(f);
-	    }
+	    /* For STD* handles, don't close stdio, since we shared the FILE *, too. */
+	    if (stdio == stdin) /* Some stdios are buggy fflush-ing inputs */
+		return 0;
+	    if (stdio == stdout || stdio == stderr)
+		return PerlIO_flush(f);
             /* Tricky - must fclose(stdio) to free memory but not close(fd)
 	       Use Sarathy's trick from maint-5.6 to invalidate the
 	       fileno slot of the FILE *
 	    */
 	    result = PerlIO_flush(f);
 	    saveerr = errno;
-    	    if (!(invalidate = PerlIOStdio_invalidate_fileno(aTHX_ stdio))) {
-	    	dupfd = PerlLIO_dup(fd);
-	    }
+	    invalidate = PerlIOStdio_invalidate_fileno(aTHX_ stdio);
+	    if (!invalidate)
+		dupfd = PerlLIO_dup(fd);
 	}
         result = PerlSIO_fclose(stdio);
 	/* We treat error from stdio as success if we invalidated
@@ -3094,10 +3102,10 @@ PerlIOStdio_close(pTHX_ PerlIO *f)
 	    errno = saveerr;
 	    result = 0;
 	}
-	if (socksfd) {
-	    /* in SOCKS case let close() determine return value */
-	    result = close(fd);
-	}
+#ifdef SOCKS5_VERSION_NAME
+	/* in SOCKS' case, let close() determine return value */
+	result = close(fd);
+#endif
 	if (dupfd) {
 	    PerlLIO_dup2(dupfd,fd);
 	    PerlLIO_close(dupfd);
@@ -3215,6 +3223,8 @@ IV
 PerlIOStdio_seek(pTHX_ PerlIO *f, Off_t offset, int whence)
 {
     FILE * const stdio = PerlIOSelf(f, PerlIOStdio)->stdio;
+    PERL_UNUSED_CONTEXT;
+
     return PerlSIO_fseek(stdio, offset, whence);
 }
 
@@ -3222,6 +3232,8 @@ Off_t
 PerlIOStdio_tell(pTHX_ PerlIO *f)
 {
     FILE * const stdio = PerlIOSelf(f, PerlIOStdio)->stdio;
+    PERL_UNUSED_CONTEXT;
+
     return PerlSIO_ftell(stdio);
 }
 
@@ -3229,10 +3241,13 @@ IV
 PerlIOStdio_flush(pTHX_ PerlIO *f)
 {
     FILE * const stdio = PerlIOSelf(f, PerlIOStdio)->stdio;
+    PERL_UNUSED_CONTEXT;
+
     if (PerlIOBase(f)->flags & PERLIO_F_CANWRITE) {
 	return PerlSIO_fflush(stdio);
     }
     else {
+	NOOP;
 #if 0
 	/*
 	 * FIXME: This discards ungetc() and pre-read stuff which is not
@@ -3254,24 +3269,32 @@ PerlIOStdio_flush(pTHX_ PerlIO *f)
 IV
 PerlIOStdio_eof(pTHX_ PerlIO *f)
 {
+    PERL_UNUSED_CONTEXT;
+
     return PerlSIO_feof(PerlIOSelf(f, PerlIOStdio)->stdio);
 }
 
 IV
 PerlIOStdio_error(pTHX_ PerlIO *f)
 {
+    PERL_UNUSED_CONTEXT;
+
     return PerlSIO_ferror(PerlIOSelf(f, PerlIOStdio)->stdio);
 }
 
 void
 PerlIOStdio_clearerr(pTHX_ PerlIO *f)
 {
+    PERL_UNUSED_CONTEXT;
+
     PerlSIO_clearerr(PerlIOSelf(f, PerlIOStdio)->stdio);
 }
 
 void
 PerlIOStdio_setlinebuf(pTHX_ PerlIO *f)
 {
+    PERL_UNUSED_CONTEXT;
+
 #ifdef HAS_SETLINEBUF
     PerlSIO_setlinebuf(PerlIOSelf(f, PerlIOStdio)->stdio);
 #else
@@ -3356,6 +3379,8 @@ PerlIOStdio_fill(pTHX_ PerlIO *f)
 {
     FILE * const stdio = PerlIOSelf(f, PerlIOStdio)->stdio;
     int c;
+    PERL_UNUSED_CONTEXT;
+
     /*
      * fflush()ing read-only streams can cause trouble on some stdio-s
      */
@@ -3702,6 +3727,8 @@ PerlIOBuf_fill(pTHX_ PerlIO *f)
     if (!b->buf)
 	PerlIO_get_base(f);     /* allocate via vtable */
 
+    assert(b->buf); /* The b->buf does get allocated via the vtable system. */
+
     b->ptr = b->end = b->buf;
 
     if (!PerlIOValid(n)) {
@@ -3962,6 +3989,8 @@ STDCHAR *
 PerlIOBuf_get_base(pTHX_ PerlIO *f)
 {
     PerlIOBuf * const b = PerlIOSelf(f, PerlIOBuf);
+    PERL_UNUSED_CONTEXT;
+
     if (!b->buf) {
 	if (!b->bufsiz)
 	    b->bufsiz = 4096;
@@ -4360,6 +4389,7 @@ PerlIOCrlf_set_ptrcnt(pTHX_ PerlIO *f, STDCHAR * ptr, SSize_t cnt)
 	ptr -= cnt;
     }
     else {
+	NOOP;
 #if 0
 	/*
 	 * Test code - delete when it works ...
@@ -5117,7 +5147,11 @@ int
 PerlIO_vsprintf(char *s, int n, const char *fmt, va_list ap)
 {
     dVAR;
+#ifdef USE_VSNPRINTF
+    const int val = vsnprintf(s, n > 0 ? n : 0, fmt, ap);
+#else
     const int val = vsprintf(s, fmt, ap);
+#endif /* #ifdef USE_VSNPRINTF */
     if (n >= 0) {
 	if (strlen(s) >= (STRLEN) n) {
 	    dTHX;