error linking lto1 for target avr

[Georg-Johann Lay]

Sean D'Epagnier schrieb:
> I have the latest gcc from svn, and with "configure --target=avr --enable-languages=c":
> 
> When building with "make" eventually I get:
> 
> gcc   -g -O2 -DIN_GCC -DCROSS_DIRECTORY_STRUCTURE  -W -Wall -Wno-narrowing -Wwrite-strings -Wcast-qual -Wstrict-prototypes -Wmissing-prototypes -Wmissing-format-attribute -pedantic -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings -Wold-style-definition -Wc++-compat -fno-common  -DHAVE_CONFIG_H  -o lto1 \
> 		lto/lto-lang.o lto/lto.o lto/lto-object.o attribs.o main.o tree-browser.o libbackend.a libcommon-target.a libcommon.a ../libcpp/libcpp.a ../libdecnumber/libdecnumber.a   -lmpc -lmpfr -lgmp -rdynamic -ldl  -L../zlib -lz libcommon.a ../libcpp/libcpp.a   ../libiberty/libiberty.a ../libdecnumber/libdecnumber.a 
> libbackend.a(avr.o): In function `avr_pgm_check_var_decl':
> /home/sean/build/gcc-svn/build-avr-nofixed/gcc/../../gcc/config/avr/avr.c:6652: undefined reference to `c_addr_space_name'
> /home/sean/build/gcc-svn/build-avr-nofixed/gcc/../../gcc/config/avr/avr.c:6649: undefined reference to `c_addr_space_name'
> libbackend.a(avr.o): In function `avr_insert_attributes':
> /home/sean/build/gcc-svn/build-avr-nofixed/gcc/../../gcc/config/avr/avr.c:6690: undefined reference to `c_addr_space_name'
> libbackend.a(avr.o): In function `avr_out_lpm':
> /home/sean/build/gcc-svn/build-avr-nofixed/gcc/../../gcc/config/avr/avr.c:2352: undefined reference to `c_addr_space_name'
> collect2: ld returned 1 exit status
> 
> avr.c uses c_addr_space_name to get the names of address spaces for 
> diagnostics.  GCC's build machinery does not arrange for this symbol
> to be available when linking lto1.  If configured with --disable-lto,
> the compiler builds, but lto is unavailable.
> 
> This issue is causing trouble for people building the avr toolchain,
> and will likely affect other targets as they adopt the use of
> c_addr_space_name.  Please suggest a fix.
> 
> Sean

In avr.c there is:

...
#include "c-family/c-common.h"
...

/* Sanity check NODE so that all pointers targeting address space
    go along with CONST qualifier.  Writing to this address spaces should
    be detected and complained about as early as possible.  */

static bool
avr_pgm_check_var_decl (tree node)
{
   const char *reason = NULL;

   addr_space_t as = ADDR_SPACE_GENERIC;

   gcc_assert (as == 0);

   if (avr_log.progmem)
     avr_edump ("%?: %t\n", node);

   switch (TREE_CODE (node))
     {
     default:
       break;

     case VAR_DECL:
       if (as = avr_nonconst_pointer_addrspace (TREE_TYPE (node)), as)
         reason = "variable";
       break;

     case PARM_DECL:
       if (as = avr_nonconst_pointer_addrspace (TREE_TYPE (node)), as)
         reason = "function parameter";
       break;

     case FIELD_DECL:
       if (as = avr_nonconst_pointer_addrspace (TREE_TYPE (node)), as)
         reason = "structure field";
       break;

     case FUNCTION_DECL:
       if (as = avr_nonconst_pointer_addrspace (TREE_TYPE (TREE_TYPE 
(node))),
           as)
         reason = "return type of function";
       break;

     case POINTER_TYPE:
       if (as = avr_nonconst_pointer_addrspace (node), as)
         reason = "pointer";
       break;
     }

   if (reason)
     {
       if (TYPE_P (node))
         error ("pointer targeting address space %qs must be const in %qT",
                c_addr_space_name (as), node);
       else
         error ("pointer targeting address space %qs must be const in %s 
%q+D",
                c_addr_space_name (as), reason, node);
     }

   return reason == NULL;
}

Is the problem some missing dependencies in the build machinery for LTO? 
Or must target.c not call functions from c-family/c-common.h?

I configure with --disable-lto because LTO fails in canadian cross 
builds, see http://sourceware.org/PR12742

Johann