[regression] function has no AST information

[ChuanqiXu9]

Reproducer:

// RUN: %clang_cc1 -fclangir %s -emit-llvm -o - | FileCheck %s

static unsigned int foo (void)
{
  return 0;
}
static unsigned int bar (void)
{
  return 0;
}

struct func {
    unsigned int (*f1) (void);
    unsigned int (*f2) (void);
};

struct func_wrapper {
    struct func f;
};

struct func_wrapper def =
{
 {
    foo
 }
};

Now it will print error: function has no AST information. This was introduced in db6b7c0. -fno-clangir-call-conv-lowering is not helpful since in populateCIRToLLVMPasses from clang/lib/CIR/Lowering/DirectToLLVM/LowerToLLVM.cpp, we will always pass true to populateCIRPreLoweringPasses.

BTW, it looks like the line

clangir/clang/lib/CIR/Dialect/Transforms/CallConvLowering.cpp

Line 36 in db6b7c0

return op.emitError("function has no AST information");

may produce pretty long (or maybe dead lock?) compile time on some larger workload:

bt-load.i.zip

This may be a separate bug but triggered by the above patch.

CC: @sitio-couto

[bcardosolopes]

Thanks for reporting this, I talked with @sitio-couto, reverting this for now