From 3433f631aa4fdee1badb78d8ac44126b711fc3e8 Mon Sep 17 00:00:00 2001
From: Graham McIntire <graham@mcintire.me>
Date: Fri, 30 Jan 2026 13:24:25 -0600
Subject: [PATCH] fix: correct library linking order in Makefile

Move -lnetsnmp to end of link command (after source files).
In GCC/Clang, library flags must come after the object files that
reference them for proper symbol resolution.

This fixes 'undefined symbol: init_snmp' runtime errors on Linux.
---
 c_src/Makefile | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/c_src/Makefile b/c_src/Makefile
index 462f899d..9d7b12d5 100644
--- a/c_src/Makefile
+++ b/c_src/Makefile
@@ -10,15 +10,15 @@ UNAME_S := $(shell uname -s)
 CFLAGS = -O3 -std=c99 -fPIC -Wall -Wextra -Wno-unused-parameter
 CFLAGS += -I$(ERL_INCLUDE_PATH)
 
-# Linker flags
-LDFLAGS = -lnetsnmp
+# Libraries (must come after source files in link command)
+LIBS = -lnetsnmp
 
 ifeq ($(UNAME_S),Darwin)
     # macOS specific flags
-    LDFLAGS += -dynamiclib -undefined dynamic_lookup
+    CFLAGS += -dynamiclib -undefined dynamic_lookup
 else
     # Linux flags
-    LDFLAGS += -shared
+    CFLAGS += -shared
 endif
 
 # Target
@@ -31,7 +31,7 @@ all: $(TARGET)
 
 $(TARGET): $(SRC)
 	@mkdir -p ../priv
-	$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $<
+	$(CC) $(CFLAGS) -o $@ $< $(LIBS)
 
 clean:
 	rm -f $(TARGET)