| Message ID | 1058a106-2dc6-095d-9f82-e5add2edce2e@gjlay.de |
|---|---|
| State | New |
| Headers | show |
On Tue, 29 Nov 2016, Georg-Johann Lay wrote: > This is a fix for a wrong warning from -Wlto-type-mismatch that reports a type > mismatch for two built-in functions. > > The avr backend has several built-ins that have the same asm name because > their assembler implementation in libgcc is exactly the same. The prototypes > might differ, however. > > This patch skips the warning for built-in types as discussed in > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78562#c6 > > Testing against avr-unknown-none, this resolves all FAILs because of that > warning, e.g. gcc.target/avr/torture/builtins-5-countlsfx.c > > Ok for trunk? Ok. Thanks, Richard. > Johann > > gcc/lto/ > PR lto/78562 > * lto-symtab.c (lto_symtab_merge_decls_2): Don't diagnose type > mismatch if the two types are built-in. > -- Richard Biener <rguenther@suse.de> SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nuernberg)
Index: lto/lto-symtab.c =================================================================== --- lto/lto-symtab.c (revision 242823) +++ lto/lto-symtab.c (working copy) @@ -655,6 +655,14 @@ lto_symtab_merge_decls_2 (symtab_node *f /* Diagnose all mismatched re-declarations. */ FOR_EACH_VEC_ELT (mismatches, i, decl) { + /* Do not diagnose two built-in declarations, there is no useful + location in that case. It also happens for AVR if two built-ins + use the same asm name because their libgcc assembler code is the + same, see PR78562. */ + if (DECL_IS_BUILTIN (prevailing->decl) + && DECL_IS_BUILTIN (decl)) + continue; + int level = warn_type_compatibility_p (TREE_TYPE (prevailing->decl), TREE_TYPE (decl), DECL_COMDAT (decl));