File binutils-maxpagesize.diff of Package cross-arm-binutils.26690

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File binutils-maxpagesize.diff of Package cross-arm-binutils.26690

commit a2267dbfc9e1dd955f78561c40f00afa9ddbe619
Author: Michael Matz <matz@suse.de>
Date:   Thu Oct 20 16:06:57 2022 +0200

x86-64: Use only one default max-page-size
    
    On x86-64 the default ELF_MAXPAGESIZE depends on a configure
    option (--disable-separate-code).  Since 9833b775
    ("PR28824, relro security issues") we use max-page-size for relro
    alignment (with a short interval, from 31b4d3a ("PR28824, relro
    security issues, x86 keep COMMONPAGESIZE relro") to its revert
    a1faa5ea, where x86-64 only used COMMONPAGESIZE as relro alignment
    target).
    
    But that means that a linker configured with --disable-separate-code
    behaves different from one configured with --enable-separate-code
    (the default), _even if using "-z {no,}separate-code" option to use
    the non-configured behaviour_ .  In particular it means that when
    configuring with --disable-separate-code the linker will produce
    binaries aligned to 2MB pages on disk, and hence generate 2MB
    executables for a hello world (and even 6MB when linked with
    "-z separate-code").
    
    Generally we can't have constants that ultimately land in static
    variables be depending on configure options if those only influence
    behaviour that is overridable by command line options.
    
    So, do away with that, make the default MAXPAGESIZE be 4k (as is default
    for most x86-64 configs anyway, as most people won't configure with
    --disable-separate-code).  If people need more they can use the
    "-z max-page-size" (with would have been required right now for a
    default configure binutils).
    
    bfd/
            * elf64-x86-64.c (ELF_MAXPAGESIZE): Don't depend on
            DEFAULT_LD_Z_SEPARATE_CODE.

diff --git a/bfd/elf64-x86-64.c b/bfd/elf64-x86-64.c
index f3b54400013..2ae8dffba0f 100644
--- a/bfd/elf64-x86-64.c
+++ b/bfd/elf64-x86-64.c
@@ -5259,11 +5259,7 @@ elf_x86_64_special_sections[]=
 #define ELF_ARCH			    bfd_arch_i386
 #define ELF_TARGET_ID			    X86_64_ELF_DATA
 #define ELF_MACHINE_CODE		    EM_X86_64
-#if DEFAULT_LD_Z_SEPARATE_CODE
-# define ELF_MAXPAGESIZE		    0x1000
-#else
-# define ELF_MAXPAGESIZE		    0x200000
-#endif
+#define ELF_MAXPAGESIZE			    0x1000
 #define ELF_COMMONPAGESIZE		    0x1000
 
 #define elf_backend_can_gc_sections	    1

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File binutils-maxpagesize.diff of Package cross-arm-binutils.26690

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