1 files changed, 43 insertions, 0 deletions
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index ae1d4f996803..0e0e5b5a72c8 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -3346,6 +3346,49 @@ static bool ignore_unreachable_insn(struct objtool_file *file, struct instructio
 	    !strcmp(insn->sec->name, ".altinstr_aux"))
 		return true;
 
+	/*
+	 * Whole archive runs might encounder dead code from weak symbols.
+	 * This is where the linker will have dropped the weak symbol in
+	 * favour of a regular symbol, but leaves the code in place.
+	 *
+	 * In this case we'll find a piece of code (whole function) that is not
+	 * covered by a !section symbol. Ignore them.
+	 */
+	if (!insn->func && lto) {
+		int size = find_symbol_hole_containing(insn->sec, insn->offset);
+		unsigned long end = insn->offset + size;
+
+		if (!size) /* not a hole */
+			return false;
+
+		if (size < 0) /* hole until the end */
+			return true;
+
+		sec_for_each_insn_continue(file, insn) {
+			/*
+			 * If we reach a visited instruction at or before the
+			 * end of the hole, ignore the unreachable.
+			 */
+			if (insn->visited)
+				return true;
+
+			if (insn->offset >= end)
+				break;
+
+			/*
+			 * If this hole jumps to a .cold function, mark it ignore too.
+			 */
+			if (insn->jump_dest && insn->jump_dest->func &&
+			    strstr(insn->jump_dest->func->name, ".cold")) {
+				struct instruction *dest = insn->jump_dest;
+				func_for_each_insn(file, dest->func, dest)
+					dest->ignore = true;
+			}
+		}
+
+		return false;
+	}
+
 	if (!insn->func)
 		return false;