Parser: assertion failure in usualArithmeticConversion

[ehaas]

The following code triggers an assertion failure:

int foo = 0xFFFFFFFFFF + 1u;

thread 15090414 panic: reached unreachable code
/Users/ehaas/source/zig/build/lib/zig/std/debug.zig:226:14: 0x10705a2f8 in std.debug.assert (arocc)
    if (!ok) unreachable; // assertion failure
             ^
/Users/ehaas/source/arocc/src/Parser.zig:3590:19: 0x107186309 in Parser.Result.usualArithmeticConversion (arocc)
            assert(b_unsigned and (@enumToInt(b_promoted.specifier) >= @enumToInt(a_promoted.specifier)));
                  ^
/Users/ehaas/source/arocc/src/Parser.zig:3345:44: 0x10714e016 in Parser.Result.adjustTypes (arocc)
            try a.usualArithmeticConversion(b, p);
                                           ^
/Users/ehaas/source/arocc/src/Parser.zig:4186:32: 0x1071bc2f0 in Parser.addExpr (arocc)
        if (try lhs.adjustTypes(minus.?, &rhs, p, if (plus != null) .add else .sub)) {
                               ^
/Users/ehaas/source/arocc/src/Parser.zig:4145:28: 0x1071bb794 in Parser.shiftExpr (arocc)
    var lhs = try p.addExpr();
                           ^
/Users/ehaas/source/arocc/src/Parser.zig:4116:30: 0x1071bafb4 in Parser.compExpr (arocc)
    var lhs = try p.shiftExpr();
                             ^
/Users/ehaas/source/arocc/src/Parser.zig:4091:29: 0x1071ba534 in Parser.eqExpr (arocc)
    var lhs = try p.compExpr();
                            ^
/Users/ehaas/source/arocc/src/Parser.zig:4071:27: 0x1071b8614 in Parser.andExpr (arocc)
    var lhs = try p.eqExpr();
                          ^
/Users/ehaas/source/arocc/src/Parser.zig:4051:28: 0x1071b1404 in Parser.xorExpr (arocc)
    var lhs = try p.andExpr();
                           ^
/Users/ehaas/source/arocc/src/Parser.zig:4031:28: 0x1071a4b74 in Parser.orExpr (arocc)
    var lhs = try p.xorExpr();
                           ^
/Users/ehaas/source/arocc/src/Parser.zig:4009:27: 0x1071853c4 in Parser.landExpr (arocc)
    var lhs = try p.orExpr();
                          ^
/Users/ehaas/source/arocc/src/Parser.zig:3987:29: 0x10714d424 in Parser.lorExpr (arocc)
    var lhs = try p.landExpr();
                            ^
/Users/ehaas/source/arocc/src/Parser.zig:3949:29: 0x10711bb94 in Parser.condExpr (arocc)
    var cond = try p.lorExpr();
                            ^
/Users/ehaas/source/arocc/src/Parser.zig:3804:29: 0x10716b2a4 in Parser.assignExpr (arocc)
    var lhs = try p.condExpr();
                            ^
/Users/ehaas/source/arocc/src/Parser.zig:2126:35: 0x107129bc7 in Parser.initializer (arocc)
        var res = try p.assignExpr();
                                  ^
/Users/ehaas/source/arocc/src/Parser.zig:1197:47: 0x1070cf447 in Parser.initDeclarator (arocc)
        var init_list_expr = try p.initializer(init_d.d.ty);
                                              ^
/Users/ehaas/source/arocc/src/Parser.zig:576:39: 0x10709c5b9 in Parser.decl (arocc)
    var init_d = (try p.initDeclarator(&decl_spec)) orelse {
                                      ^
/Users/ehaas/source/arocc/src/Parser.zig:461:19: 0x1070883ba in Parser.parse (arocc)
        if (p.decl() catch |er| switch (er) {
                  ^
/Users/ehaas/source/arocc/src/main.zig:257:32: 0x10706ac69 in processSource (arocc)
    var tree = try Parser.parse(&pp);
                               ^
/Users/ehaas/source/arocc/src/main.zig:223:22: 0x10705f211 in handleArgs (arocc)
        processSource(comp, source, builtin, user_macros) catch |e| switch (e) {
                     ^
/Users/ehaas/source/arocc/src/main.zig:41:15: 0x10705c39d in main (arocc)
    handleArgs(&comp, args) catch |err| switch (err) {
              ^
/Users/ehaas/source/zig/build/lib/zig/std/start.zig:524:29: 0x1070db5fc in std.start.callMain (arocc)
            return root.main();
                            ^
/Users/ehaas/source/zig/build/lib/zig/std/start.zig:469:12: 0x107060317 in std.start.callMainWithArgs (arocc)
    return @call(.{ .modifier = .always_inline }, callMain, .{});
           ^
/Users/ehaas/source/zig/build/lib/zig/std/start.zig:434:12: 0x107060255 in std.start.main (arocc)
    return @call(.{ .modifier = .always_inline }, callMainWithArgs, .{ @intCast(usize, c_argc), c_argv, envp });
           ^
???:?:?: 0x7fff204ecf3c in ??? (???)
???:?:?: 0x1 in ??? (???)
[1]    89704 abort      ./zig-out/bin/arocc test/cases/crash.c

[ehaas]

This can also be triggered with a comparison:

void foo(void) {
    int x = 1L == 1U;
}

[Vexu]

I have fixed this locally but forgotten to push the change.