[patch] install.texi: For gcn, recommend LLVM 15, unless gfx1100 is disabled (was: [patch] amdgcn: config.gcc - enable gfx1030 and gfx1100 multilib; add them to the docs)

[Tobias Burnus]

Hi,

Thomas Schwinge wrote:
amdgcn: config.gcc - enable gfx1030 and gfx1100 multilib; add them to 
the docs
...
Further down in that file, we state:
     @anchor{amdgcn-x-amdhsa}
     @heading amdgcn-*-amdhsa
     AMD GCN GPU target.
     
     Instead of GNU Binutils, you will need to install LLVM 13.0.1, or later, [...]

LLVM 13.0.1 may still be fine for gfx1030
('[...]/amdgcn-amdhsa/gfx1030/libgcc' does get built; I've not further
tested), but it's not sufficient for gfx1100 anymore:

Testing with the system compilers here, llvm-mc-14.0.6 also fails while 
llvm-mc-15.0.7 accepts it.

Which version of LLVM should we be recommending?

>= LLVM 15, I think. How about the following wording? It still mentions 
LLVM 13.0.1 for those that really need it but with for the default 
setup, it requires 15+.

Tobias
install.texi: For gcn, recommend LLVM 15, unless gfx1100 is disabled

gcc/ChangeLog:

	* doc/install.texi (amdgcn): Recommend LLVM 15+ and newlib 4.4+,
	but keep requiring only newlib 4.3+ and, if gfx1100 is disabled,
	LLVM 13.0.1+.

Signed-off-by: Tobias Burnus <tbur...@baylibre.com>

diff --git a/gcc/doc/install.texi b/gcc/doc/install.texi
index 5747b5a12fe..c7794439107 100644
--- a/gcc/doc/install.texi
+++ b/gcc/doc/install.texi
@@ -3927,14 +3927,15 @@ This is a synonym for @samp{x86_64-*-solaris2*}.
 @heading amdgcn-*-amdhsa
 AMD GCN GPU target.
 
-Instead of GNU Binutils, you will need to install LLVM 13.0.1, or later, and copy
+Instead of GNU Binutils, you will need to install LLVM 15, or later, and copy
 @file{bin/llvm-mc} to @file{amdgcn-amdhsa/bin/as},
 @file{bin/lld} to @file{amdgcn-amdhsa/bin/ld},
 @file{bin/llvm-nm} to @file{amdgcn-amdhsa/bin/nm}, and
 @file{bin/llvm-ar} to both @file{bin/amdgcn-amdhsa-ar} and
-@file{bin/amdgcn-amdhsa-ranlib}.
+@file{bin/amdgcn-amdhsa-ranlib}.  Note that LLVM 13.0.1 or LLVM 14 can be used
+by specifying a @code{--with-multilib-list=} that does not list @code{gfx1100}.
 
-Use Newlib (4.3.0 or newer).
+Use Newlib (4.3.0 or newer; 4.4.0 or later is recommended).
 
 To run the binaries, install the HSA Runtime from the
 @uref{https://rocm.docs.amd.com/,,ROCm Platform}, and use