From 7fce68649af1e2248f8658221bd2d29573548417 Mon Sep 17 00:00:00 2001
From: Bill Currie <bill@taniwha.org>
Date: Sun, 9 Jun 2019 16:56:20 +0900
Subject: [PATCH] Implement comma expressions

Doesn't quite work (attempt to suppress warning for return a = 3, 5;
failed).
---
 tools/qfcc/source/qc-parse.y | 20 ++++++++++++---
 tools/qfcc/test/Makefile.am  | 10 ++++++++
 tools/qfcc/test/comma-expr.r | 50 ++++++++++++++++++++++++++++++++++++
 3 files changed, 76 insertions(+), 4 deletions(-)
 create mode 100644 tools/qfcc/test/comma-expr.r

diff --git a/tools/qfcc/source/qc-parse.y b/tools/qfcc/source/qc-parse.y
index 308512b6b..c8c269d27 100644
--- a/tools/qfcc/source/qc-parse.y
+++ b/tools/qfcc/source/qc-parse.y
@@ -180,7 +180,7 @@ int yylex (void);
 %type	<symbol>	methoddef
 %type	<expr>		opt_initializer var_initializer local_def
 
-%type	<expr>		opt_init opt_expr fexpr expr element_list element
+%type	<expr>		opt_init opt_expr cexpr fexpr expr element_list element
 %type	<expr>		optional_state_expr texpr vector_expr
 %type	<expr>		statement statements compound_statement
 %type	<expr>		else label break_label continue_label
@@ -1175,7 +1175,7 @@ statement
 			break_label = $2;
 			continue_label = $3;
 		}
-	| fexpr ';'
+	| cexpr ';'
 		{
 			$$ = $1;
 		}
@@ -1227,7 +1227,7 @@ switch_block
 	;
 
 opt_init
-	: fexpr
+	: cexpr
 	| type init_var_decl_list { $$ = $2; }
 	| /* empty */
 		{
@@ -1260,7 +1260,7 @@ init_var_decl
 	;
 
 opt_expr
-	: fexpr
+	: cexpr
 	| /* empty */
 		{
 			$$ = 0;
@@ -1346,6 +1346,18 @@ texpr
 	: fexpr						{ $$ = convert_bool ($1, 1); }
 	;
 
+cexpr
+	: arg_list
+		{
+			if ($1->next) {
+				expr_t     *res = $1;
+				$1 = build_block_expr ($1->next);
+				$1->e.block.result = res;
+			}
+			$$ = $1;
+		}
+	;
+
 opt_arg_list
 	: /* emtpy */				{ $$ = 0; }
 	| arg_list					{ $$ = $1; }
diff --git a/tools/qfcc/test/Makefile.am b/tools/qfcc/test/Makefile.am
index 87742d8e0..c0d7bade0 100644
--- a/tools/qfcc/test/Makefile.am
+++ b/tools/qfcc/test/Makefile.am
@@ -31,6 +31,7 @@ fail_bins=
 test_progs_dat=\
 	chewed-alias.dat \
 	chewed-return.dat \
+	comma-expr.dat \
 	deadbool.dat \
 	fordecl.dat \
 	func-expr.dat \
@@ -89,6 +90,15 @@ chewed-return.run: Makefile build-run
 include ./$(DEPDIR)/chewed-return.Qo # am--include-marker
 r_depfiles_remade += ./$(DEPDIR)/chewed-return.Qo
 
+comma_expr_dat_SOURCES=comma-expr.r
+comma_expr_obj=$(comma_expr_dat_SOURCES:.r=.qfo)
+comma-expr.dat$(EXEEXT): $(comma_expr_obj) $(QFCC_DEP)
+	$(QFCC) $(QCFLAGS) -o $@ $(comma_expr_obj)
+comma-expr.run: Makefile build-run
+	$(srcdir)/build-run $@
+include ./$(DEPDIR)/comma-expr.Qo # am--include-marker
+r_depfiles_remade += ./$(DEPDIR)/comma-expr.Qo
+
 deadbool_dat_SOURCES=deadbool.r
 deadbool_obj=$(deadbool_dat_SOURCES:.r=.qfo)
 deadbool.dat$(EXEEXT): $(deadbool_obj) $(QFCC_DEP)
diff --git a/tools/qfcc/test/comma-expr.r b/tools/qfcc/test/comma-expr.r
new file mode 100644
index 000000000..ea145c0a2
--- /dev/null
+++ b/tools/qfcc/test/comma-expr.r
@@ -0,0 +1,50 @@
+void printf (string fmt, ...) = #0;
+
+int a = 0;
+int b = 0;
+
+int
+return_comma()
+{
+	return a = 3, 5;
+}
+
+int
+test_for_comma ()
+{
+	int         fail = 1;
+	int         count = 5;
+	int         i = -1;
+	float       j = -1;
+
+	for (i = 3, j = 5; count-- > 0; ) {
+		i += 2;
+		j += 3;
+	}
+	if (i == 13 && j == 20) {
+		fail = 0;
+	}
+
+	return fail;
+}
+
+int
+test_comma ()
+{
+	int fail = 1;
+	if (return_comma() == 5) {
+		if (a == 3) {
+			fail = 0;
+		}
+	}
+	return fail;
+}
+
+int
+main ()
+{
+	int         fail = 0;
+	fail |= test_comma ();
+	fail |= test_for_comma ();
+	return fail;
+}