https://gcc.gnu.org/g:db238f5ae70cb461f0f9d7309208c6b36616b547
commit db238f5ae70cb461f0f9d7309208c6b36616b547
Author: Palmer Dabbelt <pal...@rivosinc.com>
Date: Tue Jul 2 18:20:39 2024 -0700
RISC-V: Describe -march behavior for dependent extensions
gcc/ChangeLog:
* doc/invoke.texi: Describe -march behavior for dependent
extensions on
RISC-V.
(cherry picked from commit 70f6bc39c4b0e147a816ad1dad583f944616c367)
Diff:
---
gcc/doc/invoke.texi | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 1663ddc2252..ede749f645a 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -30927,6 +30927,10 @@ If both @option{-march} and @option{-mcpu=} are not
specified, the default for
this argument is system dependent, users who want a specific architecture
extensions should specify one explicitly.
+When the RISC-V specifications define an extension as depending on other
+extensions, GCC will implicitly add the dependent extensions to the enabled
+extension set if they weren't added explicitly.
+
@opindex mcpu
@item -mcpu=@var{processor-string}
Use architecture of and optimize the output for the given processor, specified
