Dependency update
Add array size check to sizeof() test
Sign conversion test
Handle NULL decls spels in symbol tables (f(int), etc)
Macros for endianness
l-value assignments aren't immediately fatal
Fix builtin/const-expr casting between signed and unsigned
Correct warning messages for implicit integer conversions
Backend code-gen is affected by -fno-const-fold
x86_64 backend handles comparing two V_CONST_I:s
x86_64 backend handles cast-loading a V_CONST_I or label
Backend handles casting a constant int
Both << and >> can work on signed or unsigned
sign_extend_64 tests both builtin and runtime casting
Ensure sign extension for signed -> unsigned
Zero out the top bits when sign extending to non-uint64_t
Only apply sign extension if sizes are different
Fix integral_truncate_bits() when we're truncated to ULL

This is tested via -fno-cast-with-builtin-types, which forces the intval
truncation logic to run. test2/integer_conversion/sign_extend_64.c
exposes this.
Unsigned to unsigned uses to_iv_sign_ext, to give clearer warnings
Merge branch 'fix/casting-sign-extension'