From 3e99afdbfe9a66bc5461148a4754c1e88b33fb88 Mon Sep 17 00:00:00 2001
From: Isaac Freund <mail@isaacfreund.com>
Date: Wed, 8 Mar 2023 14:21:33 +0100
Subject: [PATCH] build: add -Dpie option

It is becoming increasingly common for distributions to want to enable
PIE for all binaries and zig currently does not provide any way to do
so aside from patching the build.zig.
---
 CMakeLists.txt | 7 +++++++
 build.zig      | 2 ++
 2 files changed, 9 insertions(+)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 925fd2d639890113ee57ebdaacaa6e27be222af9..501d12889fa94526236fd7dbc2c52813e13c7443 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -827,6 +827,12 @@ else()
   set(ZIG_STATIC_ARG "")
 endif()
 
+if(CMAKE_POSITION_INDEPENDENT_CODE)
+  set(ZIG_PIE_ARG="-Dpie")
+else()
+  set(ZIG_PIE_ARG="")
+endif()
+
 set(ZIG_BUILD_ARGS
   --zig-lib-dir "${CMAKE_SOURCE_DIR}/lib"
   "-Dconfig_h=${ZIG_CONFIG_H_OUT}"
@@ -835,6 +841,7 @@ set(ZIG_BUILD_ARGS
   ${ZIG_STATIC_ARG}
   ${ZIG_NO_LIB_ARG}
   ${ZIG_SINGLE_THREADED_ARG}
+  ${ZIG_PIE_ARG}
   "-Dtarget=${ZIG_TARGET_TRIPLE}"
   "-Dcpu=${ZIG_TARGET_MCPU}"
   "-Dversion-string=${RESOLVED_ZIG_VERSION}"
diff --git a/build.zig b/build.zig
index a95c9dfb584c0ccfac2c609bdca5d07b0ec91389..12e5d014e2cae658645e4cc302547a24d9cbd76b 100644
--- a/build.zig
+++ b/build.zig
@@ -152,6 +152,7 @@ pub fn build(b: *std.Build) !void {
     const link_libc = b.option(bool, "force-link-libc", "Force self-hosted compiler to link libc") orelse (enable_llvm or only_c);
     const sanitize_thread = b.option(bool, "sanitize-thread", "Enable thread-sanitization") orelse false;
     const strip = b.option(bool, "strip", "Omit debug information");
+    const pie = b.option(bool, "pie", "Produce a Position Independent Executable");
     const value_tracing = b.option(bool, "value-tracing", "Enable extra state tracking to help troubleshoot bugs in the compiler (using the std.debug.Trace API)") orelse false;
 
     const mem_leak_frames: u32 = b.option(u32, "mem-leak-frames", "How many stack frames to print when a memory leak occurs. Tests get 2x this amount.") orelse blk: {
@@ -162,6 +163,7 @@ pub fn build(b: *std.Build) !void {
 
     const exe = addCompilerStep(b, optimize, target);
     exe.strip = strip;
+    exe.pie = pie;
     exe.sanitize_thread = sanitize_thread;
     exe.build_id = b.option(bool, "build-id", "Include a build id note") orelse false;
     exe.install();
-- 
2.54.0