On Fri, Apr 22, 2011 at 8:35 AM, Gary Funck <g...@intrepid.com> wrote: > > Recently, we tried to merge the GCC trunk into the GUPC branch > and ran into an issue caused by a recent GCC update. > The last successful merge was trunk version 172359, fyi. > > For certain UPC file scope static initializers, > a per file initialization routine is created, its address > is added to a global table (in its own section). > The UPC runtime will call all the routines listed in that > table before transferring control the user's main program. > > After the recent trial merge, we see the following on > some of our test cases: > > ../../gcc/xupc -O2 -g -fdump-ipa-cgraph -fdump-tree-cfg test25.upc -o test25 > /tmp/ccygQ8JN.o:(upc_init_array+0x0): undefined reference to > `__upc_init_decls' > > The call graph dump entry for `__upc_init_decls' is as follows: > > __upc_init_decls/80(80) @0x7ffff1eb3de0 (asm: __upc_init_decls) body finalized > called by: > calls: > References: > Refering this function: > > As expected, no explicit references have been recorded. > > The compiler routine that creates this initialization routine is > called from c_common_parse_file(): > > push_file_scope (); > c_parse_file (); > /* Generate UPC global initialization code, if required. */ > if (c_dialect_upc ()) > upc_write_global_declarations (); > pop_file_scope (); > > The routine that builds the initialization function is > upc_build_init_func() in gcc/upc/upc-act.c (on the gupc branch). > This routine does the following to build the function, > mark it as used and referenced, and to then add its address > to the initialiaztion table: > > DECL_SOURCE_LOCATION (current_function_decl) = loc; > TREE_PUBLIC (current_function_decl) = 0; > TREE_USED (current_function_decl) = 1; > DECL_SECTION_NAME (current_function_decl) = > build_string (strlen (UPC_INIT_SECTION_NAME), UPC_INIT_SECTION_NAME); > /* Swap the statement list that we've built up, > for the current statement list. */ > t_list = c_begin_compound_stmt (true); > TREE_CHAIN (stmt_list) = TREE_CHAIN (t_list); > cur_stmt_list = stmt_list; > free_stmt_list (t_list); > t_list = c_end_compound_stmt (loc, stmt_list, true); > add_stmt (t_list); > finish_function (); > gcc_assert (DECL_RTL (init_func)); > upc_init_array_section = get_section (UPC_INIT_ARRAY_SECTION_NAME, > 0, NULL); > mark_decl_referenced (init_func); > init_func_symbol = XEXP (DECL_RTL (init_func), 0); > assemble_addr_to_section (init_func_symbol, upc_init_array_section); > > In the past, setting TREE_USED() and calling mark_decl_referenced() > was sufficient to make sure that this routine was not removed from the > call graph. > > What is needed in the new scheme of things to ensure that this > initialization function stays in the call graph?
Try setting DECL_PRESERVE_P to 1. Richard. > thanks, > > - Gary >
