Fixes: opts-global.cc:75:15: runtime error: store to address 0x00000bc9be70 with insufficient space for an object of type 'char' which happens when mask == 0, len == 0 and we allocate zero elements. Eventually, result[0] is called which triggers the UBSAN.
It's newly discovered after the Siddhesh's recent patch. Cheers, Martin gcc/ChangeLog: * opts-global.cc (write_langs): Allocate at least one byte. --- gcc/opts-global.cc | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/gcc/opts-global.cc b/gcc/opts-global.cc index a18c76940f9..4f5f8cdcb98 100644 --- a/gcc/opts-global.cc +++ b/gcc/opts-global.cc @@ -61,7 +61,7 @@ write_langs (unsigned int mask) if (mask & (1U << n)) len += strlen (lang_name) + 1; - result = XNEWVEC (char, len); + result = XNEWVEC (char, MAX (1, len)); len = 0; for (n = 0; (lang_name = lang_names[n]) != 0; n++) if (mask & (1U << n)) -- 2.36.1