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diff --git a/share/man/man3/alloca.3 b/share/man/man3/alloca.3
--- a/share/man/man3/alloca.3
+++ b/share/man/man3/alloca.3
@@ -1,5 +1,6 @@
.\" Copyright (c) 1980, 1991, 1993
.\" The Regents of the University of California. All rights reserved.
+.\" Copyright (c) 2026 Aymeric Wibo <obiwac@freebsd.org>
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
@@ -25,7 +26,7 @@
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
-.Dd April 29, 2025
+.Dd February 19, 2026
.Dt ALLOCA 3
.Os
.Sh NAME
@@ -38,16 +39,14 @@
.Sh DESCRIPTION
The
.Fn alloca
-function
-allocates
+function or macro allocates
.Fa size
bytes of space in the stack frame of the caller.
This temporary space is automatically freed on
return.
.Sh RETURN VALUES
-The
.Fn alloca
-function returns a pointer to the beginning of the allocated space.
+returns a pointer to the beginning of the allocated space.
.Sh SEE ALSO
.Xr brk 2 ,
.Xr calloc 3 ,
@@ -55,24 +54,20 @@
.Xr malloc 3 ,
.Xr realloc 3
.Sh HISTORY
-The
.Fn alloca
-function appeared in
+appeared in
.At 32v .
.\" .Bx ?? .
.\" The function appeared in 32v, pwb and pwb.2 and in 3bsd 4bsd
.\" The first man page (or link to a man page that I can find at the
.\" moment is 4.3...
.Sh BUGS
-The
.Fn alloca
-function
is machine and compiler dependent;
its use is discouraged.
.Pp
-The
.Fn alloca
-function is slightly unsafe because it cannot ensure that the pointer
+is slightly unsafe because it cannot ensure that the pointer
returned points to a valid and usable block of memory.
The allocation made may exceed the bounds of the stack, or even go
further into other objects in memory, and
@@ -81,3 +76,26 @@
Avoid
.Fn alloca
with large unbounded allocations.
+.Pp
+The use of C99 variable-length arrays and
+.Fn alloca
+in the same function will cause the lifetime of
+.Fn alloca Ns 's
+storage to be limited to the block containing the
+.Fn alloca .
+For example, in the following snippet,
+.Va p Ns 's
+lifetime does not extend outside of the block, whereas it would've if
+.Va vla
+hadn't been defined or had been defined as a fixed-length array:
+.Bd -literal -offset indent
+char *p;
+{
+ const int n = 100;
+ int vla[n];
+ p = alloca(32);
+ strcpy(p, "Hello, world!");
+ printf("Inside: %s\\n", p); /* Valid. */
+}
+printf("Outside: %s\\n", p); /* Undefined. */
+.Ed

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