From e7d72b6f5303dbd0184980f00fd26ea9503bf816 Mon Sep 17 00:00:00 2001
From: Aofei Sheng <aofei@aofeisheng.com>
Date: Mon, 29 Jul 2024 08:58:13 +0800
Subject: [PATCH] build: fix `sigsetjmp` issues and ensure required libs on
 Linux

1. Handle `sigsetjmp` platform differences:
   - Separate `sigsetjmp` linkage to platform-specific files.
   - Use `__sigsetjmp` on Linux to handle `sigsetjmp` being a macro.
   - Maintain original implementation for Darwin.

2. Ensure linking of required libs:
   - Explicitly link against fundamental libs (e.g., libm, libatomic).
   - Address the fact that typical Linux linkers don't link these by
     default.
---
 c/setjmp/setjmp.go       |  3 ---
 c/setjmp/setjmp_linux.go | 12 ++++++++++++
 c/setjmp/setjmp_other.go | 12 ++++++++++++
 internal/build/build.go  |  2 ++
 4 files changed, 26 insertions(+), 3 deletions(-)
 create mode 100644 c/setjmp/setjmp_linux.go
 create mode 100644 c/setjmp/setjmp_other.go

diff --git a/c/setjmp/setjmp.go b/c/setjmp/setjmp.go
index 89c6745a1..c4bccb189 100644
--- a/c/setjmp/setjmp.go
+++ b/c/setjmp/setjmp.go
@@ -44,9 +44,6 @@ func Longjmp(env *JmpBuf, val c.Int)
 
 // -----------------------------------------------------------------------------
 
-//go:linkname Sigsetjmp C.sigsetjmp
-func Sigsetjmp(env *SigjmpBuf, savemask c.Int) c.Int
-
 //go:linkname Siglongjmp C.siglongjmp
 func Siglongjmp(env *SigjmpBuf, val c.Int)
 
diff --git a/c/setjmp/setjmp_linux.go b/c/setjmp/setjmp_linux.go
new file mode 100644
index 000000000..17bad9161
--- /dev/null
+++ b/c/setjmp/setjmp_linux.go
@@ -0,0 +1,12 @@
+//go:build linux
+
+package setjmp
+
+import (
+	_ "unsafe"
+
+	"github.com/goplus/llgo/c"
+)
+
+//go:linkname Sigsetjmp C.__sigsetjmp
+func Sigsetjmp(env *SigjmpBuf, savemask c.Int) c.Int
diff --git a/c/setjmp/setjmp_other.go b/c/setjmp/setjmp_other.go
new file mode 100644
index 000000000..a83d513d8
--- /dev/null
+++ b/c/setjmp/setjmp_other.go
@@ -0,0 +1,12 @@
+//go:build !linux
+
+package setjmp
+
+import (
+	_ "unsafe"
+
+	"github.com/goplus/llgo/c"
+)
+
+//go:linkname Sigsetjmp C.sigsetjmp
+func Sigsetjmp(env *SigjmpBuf, savemask c.Int) c.Int
diff --git a/internal/build/build.go b/internal/build/build.go
index 6de1e0c4e..aa3b8b893 100644
--- a/internal/build/build.go
+++ b/internal/build/build.go
@@ -356,6 +356,8 @@ func linkMainPkg(ctx *context, pkg *packages.Package, pkgs []*aPackage, llFiles
 			"-rpath", "$ORIGIN",
 			"-rpath", "$ORIGIN/../lib",
 			"-Xlinker", "--gc-sections",
+			"-lm",
+			"-latomic",
 			"-lpthread", // libpthread is built-in since glibc 2.34 (2021-08-01); we need to support earlier versions.
 		)
 	}