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GNU as started to emit warnings for changed sh_type or sh_flags in 2000.
GNU as>=2.35 will emit errors for most sh_type/sh_flags change, and error for entsize change.
Some cases remain warnings for legacy reasons:
.section .init_array,"ax", @progbits
.section .init_array,"ax", @init_array
# And some obscure sh_flags changes (OS/Processor specific flags)
The rationale of a diagnostic (warning or error) is that sh_type,
sh_flags or sh_entsize changes usually indicate user errors. The values
are taken from the first .section directive. Successive directives are ignored.
We just try to be rigid and emit errors for all sh_type/sh_flags/sh_entsize change.
A possible improvement in the future is to reuse
llvm-readobj/ELFDumper.cpp:getSectionTypeString so that we can name the
type in the diagnostics.
Reviewed By: psmith
Differential Revision: https://reviews.llvm.org/D73999
I've noticed that when we have all regular flags set, we print "WAEXMSILoGTx"
instead of "WAXMSILOGTCE" printed by GNU readelf.
It happens because:
1) We print SHF_EXCLUDE at the wrong place.
2) We do not recognize SHF_COMPRESSED, we print "x" instead of "C".
3) We print "o" instead of "O" for SHF_OS_NONCONFORMING.
This patch fixes differences and adds test cases.
Differential revision: https://reviews.llvm.org/D71418
We use both -long-option and --long-option in tests. Switch to --long-option for consistency.
In the "llvm-readelf" mode, -long-option is discouraged as it conflicts with grouped short options and it is not accepted by GNU readelf.
While updating the tests, change llvm-readobj -s to llvm-readobj -S to reduce confusion ("s" is --section-headers in llvm-readobj but --symbols in llvm-readelf).
llvm-svn: 359649
DWARF5 spec says about single file split case:
"The sections that do not require relocation, however, can be written
to the relocatable object (.o) file but ignored by the
the linker or they can be written to a separate DWARF object (.dwo) file
that need not be accessed by the linker."
Nice way to make linker to ignore them is to set SHF_EXCLUDE flag.
It seems to be not harmful to always set it for .dwo sections.
That is what this patch does.
Differential revision: https://reviews.llvm.org/D52303
llvm-svn: 342800
Fangrui Song