On 4/12/21 2:45 PM, Jakub Jelinek wrote:
> On Mon, Apr 12, 2021 at 02:32:35PM +0200, Martin Liška wrote:
>> +If you have an older release of binutils release, then symbol alias needs to
>
> s/binutils release/binutils/
Fixed.
>
>> +be used:
>> +
>> +@smallexample
>> +__attribute__ ((__symver__ ("foo@@VERS_2")))
>> +__attribute__ ((alias ("foo_v1")))
>> +int symver_foo_v1 (void);
>> +@end smallexample
>
> The example should show two versions of foo rather than just one, otherwise
> it will confuse users. For symbol versions which just a single symbol they
> don't need any aliases...
Very good point! Is it fine now?
Thanks,
Martin
>
> Jakub
>
>From 6dda0ec10a1b0c60e6e9afe7fc45370d0132b5e3 Mon Sep 17 00:00:00 2001
From: Martin Liska <mli...@suse.cz>
Date: Mon, 12 Apr 2021 13:42:33 +0200
Subject: [PATCH] docs: update symver attribute description
gcc/ChangeLog:
* doc/extend.texi: Be more precise in documentation
of symver attribute.
---
gcc/doc/extend.texi | 28 +++++++++++++++++++---------
1 file changed, 19 insertions(+), 9 deletions(-)
diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi
index e28e1860990..6542ada6583 100644
--- a/gcc/doc/extend.texi
+++ b/gcc/doc/extend.texi
@@ -3848,23 +3848,33 @@ foo_v1 (void)
Will produce a @code{.symver foo_v1, foo@@VERS_1} directive in the assembler
output.
-One can also define multiple version for a given symbol.
+One can also define multiple version for a given symbol
+(starting from binutils 2.35).
@smallexample
__attribute__ ((__symver__ ("foo@@VERS_2"), __symver__ ("foo@@VERS_3")))
int symver_foo_v1 (void)
@{
@}
-
-__attribute__ ((__symver__ ("bar@@VERS_2")))
-__attribute__ ((__symver__ ("bar@@VERS_3")))
-int symver_bar_v1 (void)
-@{
-@}
@end smallexample
-This example creates an alias of @code{foo_v1} with symbol name
-@code{symver_foo_v1} which will be version @code{VERS_2} of @code{foo}.
+This example creates a symbol name @code{symver_foo_v1}
+which will be version @code{VERS_2} and @code{VERS_3} of @code{foo}.
+
+If you have an older release of binutils, then symbol alias needs to
+be used:
+
+@smallexample
+__attribute__ ((__symver__ ("foo@@VERS_2")))
+int foo_v1 (void)
+{
+ return 0;
+}
+
+__attribute__ ((__symver__ ("foo@VERS_3")))
+__attribute__ ((alias ("foo_v1")))
+int symver_foo_v1 (void);
+@end smallexample
Finally if the parameter is @code{"@var{name2}@@@@@var{nodename}"} then in
addition to creating a symbol version (as if
--
2.31.1
