diff --git a/src/codegen/codegen_backend_lisp.c b/src/codegen/codegen_backend_lisp.c
index 7b4835f0..867442dd 100644
--- a/src/codegen/codegen_backend_lisp.c
+++ b/src/codegen/codegen_backend_lisp.c
@@ -162,7 +162,7 @@ static void lisp_get_struct_field_info(ParserContext *ctx, const char *type_str,
     {
         sname += 7;
     }
-    char *star = strchr(sname, '*');
+    char *star = (char *)strchr(sname, '*');
     if (star)
     {
         *star = '\0';
diff --git a/src/codegen/codegen_shared.c b/src/codegen/codegen_shared.c
index 4a2c08a5..9713f84d 100644
--- a/src/codegen/codegen_shared.c
+++ b/src/codegen/codegen_shared.c
@@ -14,7 +14,7 @@ char *strip_template_suffix(const char *name)
     {
         return NULL;
     }
-    char *lt = strchr(name, '<');
+    const char *lt = strchr(name, '<');
     if (lt)
     {
         ptrdiff_t len = lt - name;
diff --git a/src/codegen/codegen_stmt_match.c b/src/codegen/codegen_stmt_match.c
index baa73ff3..2f13d58d 100644
--- a/src/codegen/codegen_stmt_match.c
+++ b/src/codegen/codegen_stmt_match.c
@@ -16,8 +16,8 @@
 static void emit_single_pattern_cond(ParserContext *ctx, const char *pat, int id, int is_ptr)
 {
     // Check for range pattern: "start..end" or "start..=end"
-    char *range_incl = strstr(pat, "..=");
-    char *range_excl = strstr(pat, "..");
+    const char *range_incl = strstr(pat, "..=");
+    const char *range_excl = strstr(pat, "..");
 
     if (range_incl)
     {
@@ -465,7 +465,7 @@ void codegen_match_internal(ParserContext *ctx, ASTNode *node, int use_result)
                 }
                 else
                 {
-                    char *v = strstr(c->match_case.pattern, "::");
+                    char *v = (char *)strstr(c->match_case.pattern, "::");
                     if (v)
                     {
                         v += 2;
diff --git a/src/codegen/codegen_utils.c b/src/codegen/codegen_utils.c
index af521918..455e71dc 100644
--- a/src/codegen/codegen_utils.c
+++ b/src/codegen/codegen_utils.c
@@ -88,7 +88,7 @@ static void emit_c_decl(ParserContext *ctx, const char *type_str, const char *na
     else if (generic && (!bracket || generic < bracket))
     {
         char mangled_candidate[MAX_MANGLED_NAME_LEN];
-        char *gt = strchr(generic, '>');
+        char *gt = (char *)strchr(generic, '>');
         int success = 0;
 
         if (gt)
@@ -242,7 +242,7 @@ void emit_func_signature(ParserContext *ctx, ASTNode *func, const char *name_ove
             ret_str = xstrdup("void");
         }
 
-        char *fn_ptr = strstr(ret_str, "(*)");
+        char *fn_ptr = (char *)strstr(ret_str, "(*)");
 
         if (fn_ptr)
         {
diff --git a/src/platform/os.h b/src/platform/os.h
index 34b6d4d2..bc7b5bd6 100644
--- a/src/platform/os.h
+++ b/src/platform/os.h
@@ -62,9 +62,9 @@ static inline int z_is_abs_path(const char *p)
 
 static inline char *z_path_last_sep(const char *path)
 {
-    char *last_slash = strrchr(path, '/');
+    char *last_slash = (char *)strrchr(path, '/');
 #if ZC_OS_WINDOWS
-    char *last_bs = strrchr(path, '\\');
+    char *last_bs = (char *)strrchr(path, '\\');
     if (last_bs > last_slash)
     {
         return last_bs;
diff --git a/src/utils/utils.c b/src/utils/utils.c
index 9399e502..b0ab2a90 100644
--- a/src/utils/utils.c
+++ b/src/utils/utils.c
@@ -177,7 +177,7 @@ static void maybe_lock_std_root(CompilerConfig *cfg, const char *resolved)
     {
         return;
     }
-    char *std_pos = strstr(resolved, "/std/");
+    const char *std_pos = strstr(resolved, "/std/");
     if (!std_pos)
     {
         return;