wcc: modulo is integer-only; compound ops carry their operand class

Hare's rule (harec check.c binarithm): % and the bitwise/shift five
are integer-only; + - * / need numeric operands. ww grouped % with
the numeric ops, and compound assigns never op-checked at all, so
`a % b` on floats compiled half-lowered (live cs!=ww divergence),
`a %= 2.0` plain-stored the rhs (op silently dropped, both stages),
and `s += "cd"` garbled str headers. Gate both at the checker, both
stages; the cgen float-compound fallbacks and the three unknown-
compound legacy defaults (deref/global/local) demote to rule-7 hard
stops. 34 compound-on-tagged/str/slice fixtures re-pin from the old
cgen "not wired" stops to the earlier checker diagnostics; 3 new
reject fixtures pin the closed shapes.

test/wcc/data/dotfield_compound_slice/case.ww

@@ -1,4 +1,4 @@
-//ww:error "single-dot field compound on slice field"
+//ww:error "arithmetic on non-numeric type"
 // Lifted from test/wcc/949_dotfield_compound_run.c reject row "dotfld_he_slice"
 // (#34/rule-7): a compound assign on a single-dot SLICE field is unwired in
 // both stages and MUST loud-fail. The substring is the shared diagnostic body

test/wcc/data/dotfield_compound_str/case.ww

@@ -1,4 +1,4 @@
-//ww:error "single-dot field compound on str field"
+//ww:error "arithmetic on non-numeric type"
 // Lifted from test/wcc/949_dotfield_compound_run.c reject row "dotfld_he_str"
 // (#34/rule-7): a compound assign on a single-dot STR field is unwired in both
 // stages and MUST loud-fail. The substring is the shared diagnostic body —

test/wcc/data/dotfield_compound_tagged/case.ww

@@ -1,4 +1,4 @@
-//ww:error "single-dot field compound on tagged field"
+//ww:error "arithmetic on non-numeric type"
 // Lifted from test/wcc/949_dotfield_compound_run.c reject row "dotfld_he_tagged"
 // (#34/rule-7): a compound assign on a single-dot TAGGED-union field is unwired
 // in both stages and MUST loud-fail. The substring is the shared diagnostic

test/wcc/data/float_mod_reject/case.ww

@@ -0,0 +1,11 @@
+//ww:error "modulo on non-integer type"
+// % is integer-only (harec check.c binarithm BIN_MODULO). Pre-gate a
+// float % half-lowered through cgen as a live cs!=ww divergence.
+package main;
+export fn main() i32 = {
+	let a: f64 = 7.0;
+	let b: f64 = 2.0;
+	let m: f64 = a % b;
+	if (m == 1.0) { return 1; };
+	return 0;
+};

test/wcc/data/float_modeq_reject/case.ww

@@ -0,0 +1,12 @@
+//ww:error "modulo on non-integer type"
+// Compound ops carry their binary op's operand class: %= on a float
+// lvalue plain-stored the rhs pre-gate (`a %= 2.0` became `a = 2.0`,
+// silently, both stages).
+package main;
+let g: f64 = 9.0;
+export fn main() i32 = {
+	let a: f64 = 7.0;
+	a %= 2.0;
+	g %= 2.0;
+	return 0;
+};

test/wcc/data/idx_compound_str_indexed/case.ww

@@ -1,4 +1,4 @@
-//ww:error "indexed-lvalue compound on str element not wired (#133/rule-7)"
+//ww:error "arithmetic on non-numeric type"
 // Lifted from test/wcc/948_idx_compound_run.c reject row "he_str_indexed"
 // (#133-expanded rule-7): a compound assign on an indexed STR element is
 // unwired in both stages and MUST loud-fail. The substring is the FULL shared

test/wcc/data/idxfield_compound_slice/case.ww

@@ -1,4 +1,4 @@
-//ww:error "arr[i].field compound on slice field"
+//ww:error "arithmetic on non-numeric type"
 // Lifted from test/wcc/949_idxfield_compound_run.c reject row "fld_he_slice"
 // (#33/rule-7): a compound assign on an indexed-element SLICE field is unwired
 // in both stages and MUST loud-fail. The substring is the shared diagnostic

test/wcc/data/idxfield_compound_str/case.ww

@@ -1,4 +1,4 @@
-//ww:error "arr[i].field compound on str field"
+//ww:error "arithmetic on non-numeric type"
 // Lifted from test/wcc/949_idxfield_compound_run.c reject row "fld_he_str"
 // (#33/rule-7): a compound assign on an indexed-element STR field is unwired in
 // both stages and MUST loud-fail. The substring is the shared diagnostic body

test/wcc/data/idxfield_compound_tagged/case.ww

@@ -1,4 +1,4 @@
-//ww:error "arr[i].field compound on tagged field"
+//ww:error "arithmetic on non-numeric type"
 // Lifted from test/wcc/949_idxfield_compound_run.c reject row "fld_he_tagged"
 // (#33/rule-7): a compound assign on an indexed-element TAGGED-union field is
 // unwired in both stages and MUST loud-fail. The substring is the shared

test/wcc/data/r805_reject_agg_compound/case.ww

@@ -1,4 +1,4 @@
-//ww:error "assign-resolver: compound on aggregate field not wired (rule-7)"
+//ww:error "arithmetic on non-numeric type"
 package main;
 type capture = struct { content: str, start: size, end: size };
 type t = struct { pc: size, cap: capture };

test/wcc/data/r805_reject_str_compound/case.ww

@@ -1,4 +1,4 @@
-//ww:error "assign-resolver: compound on str/slice field not wired (rule-7)"
+//ww:error "arithmetic on non-numeric type"
 package main;
 type t = struct { pc: size, name: str };
 fn addname(ts: *[]t, i: size) void = { (*ts)[i].name += "x"; };

test/wcc/data/r989_tagderef_ampeq_tagged_deref/case.ww

@@ -1,4 +1,4 @@
-//ww:error "assign-resolver: tagged field not wired (rule-7)"
+//ww:error "bitwise on non-integer type"
 package main;
 export fn main() int = {
 	let v: (int | bool) = 7;

test/wcc/data/r989_tagderef_careteq_tagged_deref/case.ww

@@ -1,4 +1,4 @@
-//ww:error "assign-resolver: tagged field not wired (rule-7)"
+//ww:error "bitwise on non-integer type"
 package main;
 export fn main() int = {
 	let v: (int | bool) = 7;

test/wcc/data/r989_tagderef_lshifteq_tagged_deref/case.ww

@@ -1,4 +1,4 @@
-//ww:error "assign-resolver: tagged field not wired (rule-7)"
+//ww:error "bitwise on non-integer type"
 package main;
 export fn main() int = {
 	let v: (int | bool) = 7;

test/wcc/data/r989_tagderef_minuseq_tagged_deref/case.ww

@@ -1,4 +1,4 @@
-//ww:error "assign-resolver: tagged field not wired (rule-7)"
+//ww:error "arithmetic on non-numeric type"
 package main;
 export fn main() int = {
 	let v: (int | bool) = 7;

test/wcc/data/r989_tagderef_percenteq_tagged_deref/case.ww

@@ -1,4 +1,4 @@
-//ww:error "assign-resolver: tagged field not wired (rule-7)"
+//ww:error "modulo on non-integer type"
 package main;
 export fn main() int = {
 	let v: (int | bool) = 7;

test/wcc/data/r989_tagderef_pipeeq_tagged_deref/case.ww

@@ -1,4 +1,4 @@
-//ww:error "assign-resolver: tagged field not wired (rule-7)"
+//ww:error "bitwise on non-integer type"
 package main;
 export fn main() int = {
 	let v: (int | bool) = 7;

test/wcc/data/r989_tagderef_pluseq_tagged_deref/case.ww

@@ -1,4 +1,4 @@
-//ww:error "assign-resolver: tagged field not wired (rule-7)"
+//ww:error "arithmetic on non-numeric type"
 package main;
 export fn main() int = {
 	let v: (int | bool) = 7;

test/wcc/data/r989_tagderef_rshifteq_tagged_deref/case.ww

@@ -1,4 +1,4 @@
-//ww:error "assign-resolver: tagged field not wired (rule-7)"
+//ww:error "bitwise on non-integer type"
 package main;
 export fn main() int = {
 	let v: (int | bool) = 7;

test/wcc/data/r989_tagderef_slasheq_tagged_deref/case.ww

@@ -1,4 +1,4 @@
-//ww:error "assign-resolver: tagged field not wired (rule-7)"
+//ww:error "arithmetic on non-numeric type"
 package main;
 export fn main() int = {
 	let v: (int | bool) = 7;

test/wcc/data/r989_tagderef_stareq_tagged_deref/case.ww

@@ -1,4 +1,4 @@
-//ww:error "assign-resolver: tagged field not wired (rule-7)"
+//ww:error "arithmetic on non-numeric type"
 package main;
 export fn main() int = {
 	let v: (int | bool) = 7;

test/wcc/data/r989_tagplace_gident_pluseq/case.ww

@@ -1,4 +1,4 @@
-//ww:error "ident compound on tagged not wired (#21/rule-7)"
+//ww:error "arithmetic on non-numeric type"
 package main;
 let g: (int | bool) = 7;
 export fn main() int = { g += 1; return 0; };

test/wcc/data/r989_tagplace_gidx_careteq/case.ww

@@ -1,4 +1,4 @@
-//ww:error "indexed-lvalue compound on tagged element not wired (#133/rule-7)"
+//ww:error "bitwise on non-integer type"
 package main;
 let gs: [3](int | bool) = [1, 2, 3];
 export fn main() int = { gs[0] ^= 1; return 0; };

test/wcc/data/r989_tagplace_gidx_pluseq/case.ww

@@ -1,4 +1,4 @@
-//ww:error "indexed-lvalue compound on tagged element not wired (#133/rule-7)"
+//ww:error "arithmetic on non-numeric type"
 package main;
 let gs: [3](int | bool) = [1, 2, 3];
 export fn main() int = { gs[0] += 1; return 0; };

test/wcc/data/r989_tagplace_gidx_stareq/case.ww

@@ -1,4 +1,4 @@
-//ww:error "indexed-lvalue compound on tagged element not wired (#133/rule-7)"
+//ww:error "arithmetic on non-numeric type"
 package main;
 let gs: [3](int | bool) = [1, 2, 3];
 export fn main() int = { gs[0] *= 1; return 0; };

test/wcc/data/r989_tagplace_ident_careteq/case.ww

@@ -1,3 +1,3 @@
-//ww:error "ident compound on tagged not wired (#21/rule-7)"
+//ww:error "bitwise on non-integer type"
 package main;
 export fn main() int = { let g: (int | bool) = 7; g ^= 1; return 0; };

test/wcc/data/r989_tagplace_ident_lshifteq/case.ww

@@ -1,3 +1,3 @@
-//ww:error "ident compound on tagged not wired (#21/rule-7)"
+//ww:error "bitwise on non-integer type"
 package main;
 export fn main() int = { let g: (int | bool) = 7; g <<= 1; return 0; };

test/wcc/data/r989_tagplace_ident_minuseq/case.ww

@@ -1,3 +1,3 @@
-//ww:error "ident compound on tagged not wired (#21/rule-7)"
+//ww:error "arithmetic on non-numeric type"
 package main;
 export fn main() int = { let g: (int | bool) = 7; g -= 1; return 0; };

test/wcc/data/r989_tagplace_ident_pipeeq/case.ww

@@ -1,3 +1,3 @@
-//ww:error "ident compound on tagged not wired (#21/rule-7)"
+//ww:error "bitwise on non-integer type"
 package main;
 export fn main() int = { let g: (int | bool) = 7; g |= 1; return 0; };

test/wcc/data/r989_tagplace_ident_pluseq/case.ww

@@ -1,3 +1,3 @@
-//ww:error "ident compound on tagged not wired (#21/rule-7)"
+//ww:error "arithmetic on non-numeric type"
 package main;
 export fn main() int = { let g: (int | bool) = 7; g += 1; return 0; };

test/wcc/data/r989_tagplace_ident_slasheq/case.ww

@@ -1,3 +1,3 @@
-//ww:error "ident compound on tagged not wired (#21/rule-7)"
+//ww:error "arithmetic on non-numeric type"
 package main;
 export fn main() int = { let g: (int | bool) = 7; g /= 1; return 0; };

test/wcc/data/r989_tagplace_ident_stareq/case.ww

@@ -1,3 +1,3 @@
-//ww:error "ident compound on tagged not wired (#21/rule-7)"
+//ww:error "arithmetic on non-numeric type"
 package main;
 export fn main() int = { let g: (int | bool) = 7; g *= 1; return 0; };

test/wcc/data/r989_tagplace_lidx_lshifteq/case.ww

@@ -1,4 +1,4 @@
-//ww:error "indexed-lvalue compound on tagged element not wired (#133/rule-7)"
+//ww:error "bitwise on non-integer type"
 package main;
 export fn main() int = {
 	let a: [3](int | bool) = [1, 2, 3];

test/wcc/data/r989_tagplace_lidx_minuseq/case.ww

@@ -1,4 +1,4 @@
-//ww:error "indexed-lvalue compound on tagged element not wired (#133/rule-7)"
+//ww:error "arithmetic on non-numeric type"
 package main;
 export fn main() int = {
 	let a: [3](int | bool) = [1, 2, 3];

test/wcc/data/r989_tagplace_lidx_pipeeq/case.ww

@@ -1,4 +1,4 @@
-//ww:error "indexed-lvalue compound on tagged element not wired (#133/rule-7)"
+//ww:error "bitwise on non-integer type"
 package main;
 export fn main() int = {
 	let a: [3](int | bool) = [1, 2, 3];

test/wcc/data/r989_tagplace_lidx_pluseq/case.ww

@@ -1,4 +1,4 @@
-//ww:error "indexed-lvalue compound on tagged element not wired (#133/rule-7)"
+//ww:error "arithmetic on non-numeric type"
 package main;
 export fn main() int = {
 	let a: [3](int | bool) = [1, 2, 3];

test/wcc/data/str_pluseq_reject/case.ww

@@ -0,0 +1,9 @@
+//ww:error "arithmetic on non-numeric type"
+// += needs numeric operands; `s += "cd"` passed the op-blind
+// assignability check and cgen garbled the header words silently.
+package main;
+export fn main() i32 = {
+	let s: str = "ab";
+	s += "cd";
+	return 0;
+};