https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95918
--- Comment #9 from David Edelsohn <dje at gcc dot gnu.org> --- This set of regexps works for me: ! { dg-final { scan-tree-dump { \(\*var\.str2\)\[1\]{lb: 1 sz: 4} = "(d\\x00\\x 00|\\x00\\x00\\x00d)"\[1\]{lb: 1 sz: 4};} "original" } } ! { dg-final { scan-tree-dump { __builtin_memmove \(\(void \*\) &\(\*var.str2\) \[2\]{lb: 1 sz: 4}, \(void \*\) &"(e\\x00\\x00\\x00f\\x00\\x00|\\x00\\x00\\x00e\ \x00\\x00\\x00f)"\[1\]{lb: 1 sz: 4}, 8\);} "original" } } ! { dg-final { scan-tree-dump { \(\*var.str2\)\[4\]{lb: 1 sz: 4} = "(\\x00\\xf6 \\x01|\\x00\\x01\\xf6)"\[1\]{lb: 1 sz: 4};} "original" } } ! { dg-final { scan-tree-dump { \(\*var.str2\)\[5\]{lb: 1 sz: 4} = "(\\b\\xf6\\ x01|\\x00\\x01\\xf6\\b)"\[1\]{lb: 1 sz: 4};} "original" } } Okay?