diff options
Diffstat (limited to 'gcc/stor-layout.c')
| -rw-r--r-- | gcc/stor-layout.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/gcc/stor-layout.c b/gcc/stor-layout.c index f657463..fe9ed2c 100644 --- a/gcc/stor-layout.c +++ b/gcc/stor-layout.c @@ -389,7 +389,15 @@ layout_decl (decl, known_align) DECL_BIT_FIELD_TYPE (decl) = DECL_BIT_FIELD (decl) ? type : 0; if (maximum_field_alignment != 0) DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl), maximum_field_alignment); - else if (DECL_PACKED (decl)) + + /* If the field is of variable size, we can't misalign it since we + have no way to make a temporary to align the result. But this + isn't an issue if the decl is not addressable. Likewise if it + is of unknown size. */ + else if (DECL_PACKED (decl) + && (DECL_NONADDRESSABLE_P (decl) + || DECL_SIZE_UNIT (decl) == 0 + || TREE_CODE (DECL_SIZE_UNIT (decl)) == INTEGER_CST)) { DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl), BITS_PER_UNIT); DECL_USER_ALIGN (decl) = 0; |