cmd/asm, cmd/compile, doc: document -spectre flags
Most of the docs are in the new wiki page
https://golang.org/wiki/Spectre.
Updates #37419.
Change-Id: I6e8f76670593c089de895e1665b41d874f879df9
Reviewed-on: https://go-review.googlesource.com/c/go/+/236599
Reviewed-by: Austin Clements <austin@google.com>
diff --git a/doc/go1.15.html b/doc/go1.15.html
index 7a19242..d178887 100644
--- a/doc/go1.15.html
+++ b/doc/go1.15.html
@@ -246,7 +246,11 @@
</p>
<p><!-- CL 222661 -->
- TODO: -spectre flags
+ Go 1.15 adds a <code>-spectre</code> flag to both the
+ compiler and the assembler, to allow enabling Spectre mitigations.
+ These should almost never be needed and are provided mainly as a
+ “defense in depth” mechanism.
+ See the <a href="https://github.com/golang/go/wiki/Spectre">Spectre wiki page</a> for details.
</p>
<h2 id="linker">Linker</h2>
@@ -276,7 +280,7 @@
These changes are part of a multi-release project
to <a href="https://golang.org/s/better-linker">modernize the Go
linker</a>, meaning that there will be additional linker
- improvements expected in future releases.
+ improvements expected in future releases.
</p>
<h2 id="library">Core library</h2>
diff --git a/src/cmd/asm/doc.go b/src/cmd/asm/doc.go
index 8bf0aca..4a0c785 100644
--- a/src/cmd/asm/doc.go
+++ b/src/cmd/asm/doc.go
@@ -33,14 +33,17 @@
Dump instructions as they are parsed.
-dynlink
Support references to Go symbols defined in other shared libraries.
+ -gensymabis
+ Write symbol ABI information to output file. Don't assemble.
-o file
Write output to file. The default is foo.o for /a/b/c/foo.s.
-shared
Generate code that can be linked into a shared library.
+ -spectre list
+ Enable spectre mitigations in list (all, ret).
-trimpath prefix
Remove prefix from recorded source file paths.
- -gensymabis
- Write symbol ABI information to output file. Don't assemble.
+
Input language:
The assembler uses mostly the same syntax for all architectures,
diff --git a/src/cmd/compile/doc.go b/src/cmd/compile/doc.go
index 36dd4bb..46d47220 100644
--- a/src/cmd/compile/doc.go
+++ b/src/cmd/compile/doc.go
@@ -107,6 +107,8 @@
Warn about composite literals that can be simplified.
-shared
Generate code that can be linked into a shared library.
+ -spectre list
+ Enable spectre mitigations in list (all, index, ret).
-traceprofile file
Write an execution trace to file.
-trimpath prefix
