From d5621504b0e2160fa44991fc4180165584d72819 Mon Sep 17 00:00:00 2001
From: Robin Voetter <robin@voetter.nl>
Date: Fri, 17 Dec 2021 18:50:38 +0100
Subject: [PATCH] stage2: save and restore parameters when resolving inline
 bodies

This caused zirParam instructions of parent blocks to be present in
inline analyzed blocks, and so function prototypes declared in the
inline blocks would also gain and add to the parameters in the
parent block.

Only block and block_inline are affected in this commit, as prototypes
and declarations are always generated in block_inline. This might need
to be resolved in a more general way at some point.
---
 src/Sema.zig | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/src/Sema.zig b/src/Sema.zig
index bdbdea42e7..174e038db4 100644
--- a/src/Sema.zig
+++ b/src/Sema.zig
@@ -940,6 +940,15 @@ pub fn analyzeBody(
                 const inst_data = datas[inst].pl_node;
                 const extra = sema.code.extraData(Zir.Inst.Block, inst_data.payload_index);
                 const inline_body = sema.code.extra[extra.end..][0..extra.data.body_len];
+                // If this block contains a function prototype, we need to reset the
+                // current list of parameters and restore it later.
+                // Note: this probably needs to be resolved in a more general manner.
+                const prev_params = block.params;
+                block.params = .{};
+                defer {
+                    block.params.deinit(sema.gpa);
+                    block.params = prev_params;
+                }
                 const break_inst = try sema.analyzeBody(block, inline_body);
                 const break_data = datas[break_inst].@"break";
                 if (inst == break_data.block_inst) {
@@ -953,6 +962,15 @@ pub fn analyzeBody(
                 const inst_data = datas[inst].pl_node;
                 const extra = sema.code.extraData(Zir.Inst.Block, inst_data.payload_index);
                 const inline_body = sema.code.extra[extra.end..][0..extra.data.body_len];
+                // If this block contains a function prototype, we need to reset the
+                // current list of parameters and restore it later.
+                // Note: this probably needs to be resolved in a more general manner.
+                const prev_params = block.params;
+                block.params = .{};
+                defer {
+                    block.params.deinit(sema.gpa);
+                    block.params = prev_params;
+                }
                 const break_inst = try sema.analyzeBody(block, inline_body);
                 const break_data = datas[break_inst].@"break";
                 if (inst == break_data.block_inst) {