From: Simon Marchi <simon.marchi@polymtl.ca>
To: "gdb-patches@sourceware.org" <gdb-patches@sourceware.org>
Subject: -Wtautological-bitwise-compare error in arm-tdep.c
Date: Fri, 15 May 2020 16:32:00 -0400 [thread overview]
Message-ID: <fa18d42b-0365-762a-76af-589223cc05d2@polymtl.ca> (raw)
We get this error in arm-tdep.c when building with clang 11:
CXX arm-tdep.o
/home/smarchi/src/binutils-gdb/gdb/arm-tdep.c:934:29: error: bitwise comparison always evaluates to false [-Werror,-Wtautological-bitwise-compare]
else if ((insn & 0xffb0) == 0xe950 /* ldrd Rt, Rt2,
~~~~~~~~~~~~~~~~^~~~~~~~~
Indeed, this can never evaluate to true. I tried to look at what the condition
should be, but it's a bit too deep into ARM instruction encoding for me. I am
pretty sure that the corresponding section in the ARM Architecture Reference
Manual [1] is F3.1.15, if somebody wants to take a stab at it.
Simon
[1] https://static.docs.arm.com/ddi0487/fb/DDI0487F_b_armv8_arm.pdf
next reply other threads:[~2020-05-15 20:32 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-15 20:32 Simon Marchi [this message]
2020-05-15 20:41 ` Luis Machado
2020-05-15 20:57 ` Simon Marchi
2020-05-25 13:08 ` Luis Machado
2020-05-25 13:49 ` Simon Marchi
2020-05-25 13:51 ` Luis Machado
2020-05-26 9:45 ` Alan Hayward
2020-05-26 12:17 ` Luis Machado
2020-05-26 16:10 ` Alan Hayward
2020-05-27 12:43 ` Luis Machado
2020-05-27 14:00 ` Simon Marchi
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