From 8cd3c069d662d12e727f75bb40bbfdc5d05e0308 Mon Sep 17 00:00:00 2001
From: Robert O'Callahan <rocallahan@google.com>
Date: Fri, 12 Sep 2025 06:13:13 +0000
Subject: [PATCH] Use C++ stringf machinery in verilog_error

---
 frontends/verilog/verilog_error.cc | 35 +++++-------------------------
 frontends/verilog/verilog_error.h  | 16 ++++++++++++--
 2 files changed, 20 insertions(+), 31 deletions(-)

diff --git a/frontends/verilog/verilog_error.cc b/frontends/verilog/verilog_error.cc
index 491b8c7f5..b968b3e21 100644
--- a/frontends/verilog/verilog_error.cc
+++ b/frontends/verilog/verilog_error.cc
@@ -32,37 +32,14 @@ USING_YOSYS_NAMESPACE
  */
 
 [[noreturn]]
-static void verr_at(std::string filename, int begin_line, char const *fmt, va_list ap)
+void VERILOG_FRONTEND::formatted_err_at_loc(Location loc, std::string str)
 {
-    char buffer[1024];
-    char *p = buffer;
-    p += vsnprintf(p, buffer + sizeof(buffer) - p, fmt, ap);
-    p += snprintf(p, buffer + sizeof(buffer) - p, "\n");
-    YOSYS_NAMESPACE_PREFIX log_file_error(filename, begin_line, "%s", buffer);
-    exit(1);
+    YOSYS_NAMESPACE_PREFIX log_file_error(loc.begin.filename ? *(loc.begin.filename) : "UNKNOWN", loc.begin.line,
+            "%s\n", std::move(str));
 }
 
-static void vwarn_at(std::string filename, int begin_line, char const *fmt, va_list ap)
+void VERILOG_FRONTEND::formatted_warn_at_loc(Location loc, std::string str)
 {
-    char buffer[1024];
-    char *p = buffer;
-    p += vsnprintf(p, buffer + sizeof(buffer) - p, fmt, ap);
-    p += snprintf(p, buffer + sizeof(buffer) - p, "\n");
-    YOSYS_NAMESPACE_PREFIX log_file_warning(filename, begin_line, "%s", buffer);
+    YOSYS_NAMESPACE_PREFIX log_file_warning(loc.begin.filename ? *(loc.begin.filename) : "UNKNOWN", loc.begin.line,
+            "%s\n", std::move(str));
 }
-
-[[noreturn]]
-void VERILOG_FRONTEND::err_at_loc(Location loc, char const *fmt, ...)
-{
-    va_list args;
-    va_start(args, fmt);
-    verr_at(loc.begin.filename ? *(loc.begin.filename) : "UNKNOWN", loc.begin.line, fmt, args);
-}
-void VERILOG_FRONTEND::warn_at_loc(Location loc, char const *fmt, ...)
-{
-    va_list args;
-    va_start(args, fmt);
-    vwarn_at(loc.begin.filename ? *(loc.begin.filename) : "UNKNOWN", loc.begin.line, fmt, args);
-    va_end(args);
-}
-
diff --git a/frontends/verilog/verilog_error.h b/frontends/verilog/verilog_error.h
index b36de19b8..ede489b26 100644
--- a/frontends/verilog/verilog_error.h
+++ b/frontends/verilog/verilog_error.h
@@ -10,8 +10,20 @@ YOSYS_NAMESPACE_BEGIN
 namespace VERILOG_FRONTEND
 {
     [[noreturn]]
-    void err_at_loc(Location loc, char const *fmt, ...);
-    void warn_at_loc(Location loc, char const *fmt, ...);
+    void formatted_err_at_loc(Location loc, std::string str);
+    template <typename... Args>
+    [[noreturn]]
+    void err_at_loc(Location loc, FmtString<TypeIdentity<Args>...> fmt, const Args &... args)
+    {
+        formatted_err_at_loc(std::move(loc), fmt.format(args...));
+    }
+
+    void formatted_warn_at_loc(Location loc, std::string str);
+    template <typename... Args>
+    void warn_at_loc(Location loc, FmtString<TypeIdentity<Args>...> fmt, const Args &... args)
+    {
+        formatted_warn_at_loc(std::move(loc), fmt.format(args...));
+    }
 };
 
 YOSYS_NAMESPACE_END