scc

commit b27864c02e4c06be0bac3a0c673d85bb3a281b71
parent 76a7e8501aac08ca649752263c991b03a3a73d7b
Author: Roberto E. Vargas Caballero <k0ga@shike2.net>
Date:   Thu, 26 Mar 2026 12:11:27 +0100

cc1: Emit hidden variables for compound literals

Compound literals are just hidden local auto variables and we can reuse
the autoinit() function to emit them.

Diffstat:
M
src/cmd/scc-cc/cc1/cc1.h
 | 
1
+
M
src/cmd/scc-cc/cc1/expr.c
 | 
7
+++++--
M
src/cmd/scc-cc/cc1/init.c
 | 
19
+++++++++++++------
M
tests/cc/execute/0177-literal.c
 | 
18
++++++++++++++----
A
tests/cc/execute/0252-literal.c
 | 
31
+++++++++++++++++++++++++++++++
M
tests/cc/execute/scc-tests.lst
 | 
5
+++--

6 files changed, 67 insertions(+), 14 deletions(-)
diff --git a/src/cmd/scc-cc/cc1/cc1.h b/src/cmd/scc-cc/cc1/cc1.h
@@ -510,6 +510,7 @@ int power2node(Node *, int *);
 /* init.c */
 void initializer(Symbol *sym, Type *tp);
 Node *initlist(Type *tp);
+Symbol *autoinit(Symbol *, Type *, Node *);
 
 /* cpp.c */
 void icpp(void);
diff --git a/src/cmd/scc-cc/cc1/expr.c b/src/cmd/scc-cc/cc1/expr.c
@@ -971,8 +971,11 @@ cast(void)
 		tp = typename();
 		expect(')');
 
-		if (yytoken == '{')
-			return decay(initlist(tp));
+		if (yytoken == '{') {
+			np = initlist(tp);
+			np = varnode(autoinit(NULL, tp, np));
+			return decay(np);
+		}
 
 		switch (tp->op) {
 		case ARY:
diff --git a/src/cmd/scc-cc/cc1/init.c b/src/cmd/scc-cc/cc1/init.c
@@ -454,12 +454,18 @@ emitstrings(Node *np)
 	emitstrings(np->right);
 }
 
-static void
-autoinit(Symbol *sym, Node *np)
+Symbol *
+autoinit(Symbol *sym, Type *tp, Node *np)
 {
 	unsigned long long a;
 	Symbol *hidden;
-	Type *tp = sym->type;
+
+	if (!sym) {
+		sym = newsym(NS_IDEN, NULL);
+		sym->id = newid();
+		sym->type = tp;
+		sym->flags |= SAUTO;
+	}
 
 repeat:
 	switch (tp->op) {
@@ -479,8 +485,7 @@ repeat:
 			emitstrings(np);
 			emit(ODECL, sym);
 			autocomp(sym, np, np->type, &a);
-			return;
-
+			break;
 		}
 		hidden = newsym(NS_IDEN, NULL);
 		hidden->id = newid();
@@ -497,6 +502,8 @@ repeat:
 		emit(OEXPR, np);
 		break;
 	}
+
+	return sym;
 }
 
 void
@@ -528,6 +535,6 @@ initializer(Symbol *sym, Type *tp)
 		errorp("'%s' has both '%s' and initializer",
 		       sym->name, (flags&SEXTERN) ? "extern" : "typedef");
 	} else {
-		autoinit(sym, np);
+		autoinit(sym, np->type, np);
 	}
 }
diff --git a/tests/cc/execute/0177-literal.c b/tests/cc/execute/0177-literal.c
@@ -1,9 +1,19 @@
-int boo(int *p)
+int
+cmp(int *v)
 {
-	return (p[1] == 2) ? 0 : 1;
+	if (v[0] != 1)
+		return 1;
+	if (v[1] != 2)
+		return 2;
+	if (v[2] != 3)
+		return 3;
+	if (v[3] != 4)
+		return 4;
+	return 0;
 }
 
-int main()
+int
+main(void)
 {
-	return boo((int[]) {0, 2});
+	return cmp((int []) {1, 2, 3, 4});
 }
diff --git a/tests/cc/execute/0252-literal.c b/tests/cc/execute/0252-literal.c
@@ -0,0 +1,31 @@
+int
+cmp(int *v)
+{
+	if (v[0] != 1)
+		return 1;
+	if (v[1] != 2)
+		return 2;
+	if (v[2] != 3)
+		return 3;
+	if (v[3] != 4)
+		return 4;
+	if (v[4] != 69)
+		return 5;
+	return 0;
+}
+
+int
+set(int *a)
+{
+	*a = 69;
+	return 1;
+}
+
+int
+main(void)
+{
+	int a;
+
+	set(&a);
+	return cmp((int []) {1, 2, 3, 4, a});
+}
diff --git a/tests/cc/execute/scc-tests.lst b/tests/cc/execute/scc-tests.lst
@@ -167,7 +167,7 @@
 0174-decay.c
 0175-defined.c
 0176-macro.c
-0177-literal.c [TODO]
+0177-literal.c
 0178-include.c
 0179-sizeof.c
 0180-incomplete.c
@@ -203,7 +203,7 @@
 0210-flexible.c
 0211-enum.c
 0212-krtypes.c
-0213-decay.c [TODO]
+0213-decay.c
 0214-va_copy.c
 0215-ret_struct.c
 0216-initialize.c
@@ -242,3 +242,4 @@
 0249-mod.c
 0250-div.c
 0251-mul.c
+0252-literal.c