2 Commits

Author SHA1 Message Date
yronglin
8392f1cc78 Fix __builtin_assume_aligned incorrect type descriptor and C++ object polymorphic address
Fix __builtin_assume_aligned incorrect type descriptor

example from @rsmith

struct A { int n; };
struct B { int n; };
struct C : A, B {};

void *f(C *c) {
  // Incorrectly returns `c` rather than the address of the B base class.
  return __builtin_assume_aligned((B*)c, 8);
}

Differential Revision: https://reviews.llvm.org/D133583
2022-09-20 12:35:18 -04:00
Erich Keane
41af971375 Limit types of builtins that can be redeclared.
As reported here: https://bugs.llvm.org/show_bug.cgi?id=37033
Any usage of a builtin function that uses a va_list by reference
will cause an assertion when redeclaring it.

After discussion in the review, it was concluded that the correct
way of accomplishing this fix is to make attempts to redeclare certain
builtins an error. Unfortunately, doing this limitation for all builtins
is likely a breaking change, so this commit simply limits it to
types with custom type checking and those that take a reference.

Two tests needed to be updated to make this work.

Differential Revision: https://reviews.llvm.org/D45383

llvm-svn: 330160
2018-04-16 21:30:08 +00:00