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Date: Mon, 14 Nov 2005 21:47:00 -0000
Subject: [Bug c/24863]  New: New __attribute__((alias("target"))) requirement break aliasing assembler functions
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The new requirement for (weak) symbol aliasing:

<Quote from GCC 4.0.x release notes>
Given __attribute__((alias("target"))) it is now an error if target is not a
symbol, defined in the same translation unit. This also applies to aliases
created by #pragma weak alias=target. This is because it's meaningless to
define
an alias to an undefined symbol. On Solaris, the native assembler would have
caught this error, but GNU as does not.
</Quote>

breaks compilation of code like this (example from an sh-elf target, but the
effect is architecture-independent):


extern __attribute__((weak,alias("UIE11"))) void NMI(void);
void UIE11 (void);

asm(
    "_UIE11:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\t\n"
);


which is perfectly valid and worked in all of gcc 3.0.x, gcc 3.3.x and gcc
3.4.x


-- 
           Summary: New __attribute__((alias("target"))) requirement break
                    aliasing assembler functions
           Product: gcc
           Version: 4.0.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: arnold-j at t-online dot de


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24863