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From: Andreas Schwab <schwab@suse.de>
To: Khem Raj <raj.khem@gmail.com>
Cc: grub-devel@gnu.org,  Daniel Kiper <daniel.kiper@oracle.com>,  Chester
 Lin <clin@suse.com>,  Nikita Ermakov <arei@altlinux.org>,  Alistair
 Francis <alistair.francis@wdc.com>
Subject: Re: [PATCH] RISC-V: Restore the typcast to 64bit type
References: <20210328224913.799167-1-raj.khem@gmail.com>
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Date: Mon, 29 Mar 2021 12:24:23 +0200
In-Reply-To: <20210328224913.799167-1-raj.khem@gmail.com> (Khem Raj's message
 of "Sun, 28 Mar 2021 15:49:13 -0700")
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On Mär 28 2021, Khem Raj wrote:

> this makes the type promotions clear and explicit
> It was already typecasted to long but was accidentally dropped in [1]

Note that long is 32-bit on riscv32, so the title is misleading (there
was no cast to 64-bit type before).  The cast really was a no-op, as it
didn't change the resulting type.  The issue is that the types of
sym_addr, target_section_addr and offset are Elf_Addr (aka Elf32_Addr),
which is an unsigned type (image_target->vaddr_offset is signed, but not
wider than Elf32_Addr, so it doesn't change the overall type).  Thus
when the result of the expression is extended to grub_int64_t it is
always a positive value instead of the desired sign-extended one.

> which stated to cause failures on riscv32 as reported in [2]

Most likely the missing addend masked the error.

Andreas.

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
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