https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71378
--- Comment #2 from Martin Liška <marxin at gcc dot gnu.org> --- Reduced test-case: $ cat tc.ii class A { public: int GetLen(); }; class B { A s_MDSPartIDStr; void FillLoadPartitionInfo(); }; void B::FillLoadPartitionInfo() { char a[s_MDSPartIDStr.GetLen()] = ""; } $ (gdb) p debug_tree(decl) <var_decl 0x7ffff6a21870 *.LC0 type <array_type 0x7ffff6a13738 type <integer_type 0x7ffff68855e8 char sizes-gimplified public string-flag type_6 QI size <integer_cst 0x7ffff6881f48 constant 8> unit size <integer_cst 0x7ffff6881f60 constant 1> align 8 symtab 0 alias set -1 canonical type 0x7ffff68855e8 precision 8 min <integer_cst 0x7ffff6881f90 -128> max <integer_cst 0x7ffff6881fc0 127> pointer_to_this <pointer_type 0x7ffff68a9b28>> sizes-gimplified BLK size <var_decl 0x7ffff6a21120 D.2578 type <integer_type 0x7ffff68852a0 bitsizetype> unsigned ignored TI file /home/marxin/Programming/testcases/PR71378/tc.ii line 9 col 40 size <integer_cst 0x7ffff6881ea0 constant 128> unit size <integer_cst 0x7ffff6881eb8 constant 16> align 128 context <function_decl 0x7ffff6a16600 FillLoadPartitionInfo> chain <var_decl 0x7ffff6a211b0 D.2579>> unit size <var_decl 0x7ffff6a211b0 D.2579 type <integer_type 0x7ffff68851f8 sizetype> unsigned ignored DI file /home/marxin/Programming/testcases/PR71378/tc.ii line 9 col 40 size <integer_cst 0x7ffff6881e58 constant 64> unit size <integer_cst 0x7ffff6881e70 constant 8> align 64 context <function_decl 0x7ffff6a16600 FillLoadPartitionInfo> chain <var_decl 0x7ffff6a21240 D.2580>> align 8 symtab 0 alias set -1 structural equality domain <integer_type 0x7ffff6a13690 type <integer_type 0x7ffff68851f8 sizetype> sizes-gimplified type_6 DI size <integer_cst 0x7ffff6881e58 64> unit size <integer_cst 0x7ffff6881e70 8> align 64 symtab 0 alias set -1 structural equality precision 64 min <integer_cst 0x7ffff6881e88 0> max <var_decl 0x7ffff6a21090 D.2577>> pointer_to_this <pointer_type 0x7ffff6a13dc8>> readonly addressable asm_written static ignored in-constant-pool BLK file (null) line 0 col 0 size <var_decl 0x7ffff6a21120 D.2578> unit size <var_decl 0x7ffff6a211b0 D.2579> align 256 initial <string_cst 0x7ffff69f2ee8>> Problem is that unit size of the VAR_DECL is not an integer constant.