From 0ea834c1156305a0a2a64598ac610f4d0a232431 Mon Sep 17 00:00:00 2001 From: Mark Mitchell Date: Tue, 12 Jun 2001 11:17:09 +0000 Subject: expr.c (store_field): Don't set MEM_ALIAS_SET for a field in a structure at a variable address. * expr.c (store_field): Don't set MEM_ALIAS_SET for a field in a structure at a variable address. From-SVN: r43256 --- gcc/expr.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) (limited to 'gcc/expr.c') diff --git a/gcc/expr.c b/gcc/expr.c index a7b0ff4..9666568 100644 --- a/gcc/expr.c +++ b/gcc/expr.c @@ -5327,7 +5327,16 @@ store_field (target, bitsize, bitpos, mode, exp, value_mode, (bitpos / BITS_PER_UNIT)))); MEM_SET_IN_STRUCT_P (to_rtx, 1); - MEM_ALIAS_SET (to_rtx) = alias_set; + /* If the address of the structure varies, then it might be on + the stack. And, stack slots may be shared across scopes. + So, two different structures, of different types, can end up + at the same location. We will give the structures alias set + zero; here we must be careful not to give non-zero alias sets + to their fields. */ + if (!rtx_varies_p (addr, /*for_alias=*/0)) + MEM_ALIAS_SET (to_rtx) = alias_set; + else + MEM_ALIAS_SET (to_rtx) = 0; return store_expr (exp, to_rtx, value_mode != VOIDmode); } -- cgit v1.1