bundled x86 assembler chokes on expressions involving division about sdk-ng HOT 5 CLOSED

I tried this test on fedora and get:

[galak@spiff zephyr]$ objdump -d test.o

test.o:     file format elf64-x86-64


Disassembly of section .text:

0000000000000000 <.text>:
   0:	b8 00 00 00 00       	mov    $0x0,%eax

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@galak Sorry, there was a formatting error in the description, which left off the X=(512/4) bit (which is crucial).

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@gnuless the 2.32 you built from source, what config options did you give it?

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the 2.32 you built from source, what config options did you give it?

Oh, just very vanilla. ./configure --prefix=/home/charles/binutils-test or similar. On an Ubuntu 18.04.3 x86_64 system, then make install and test.

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Seems like binutils treats slashes as start of a comment on i386, from: https://sourceware.org/binutils/docs-2.33.1/as/i386_002dChars.html#i386_002dChars

If the --divide command-line option has not been specified then the ‘/’ character appearing anywhere on a line also introduces a line comment.

Adding --divide to x86_64-zephyr-elf-as fixes the error. Running objdump with the resulting object file shows the same output.

This is due to the #define SVR4_COMMENT_CHARS and i386_comment_chars variable in gas/config/tc-i386.c (line 440). According to the #if, forward slash is considered the beginning of a comment when the target is not a Linux base system (among others). Therefore, locally compiled version, as it is targeting a Linux system, would not consider forward slash as the start of a comment. So this is intended behavior of binutils.

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