[Bug fortran/64528] [5 Regression] ICE: in process_constraint, at tree-ssa-structalias.c:3002 with -O -fno-tree-ccp -fno-tree-dce

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64528

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
Indeed:

/* In a VAR_DECL, PARM_DECL or FIELD_DECL, or any kind of ..._REF node,
   nonzero means it may not be the lhs of an assignment.
   Nonzero in a FUNCTION_DECL means this function should be treated
   as "const" function (can only read its arguments).  */
#define TREE_READONLY(NODE) (NON_TYPE_CHECK (NODE)->base.readonly_flag)

OTOH the stmt verifier should better catch this error as well.