From 5920d777be95de6c5d6f6586bf2d34977ffd9db7 Mon Sep 17 00:00:00 2001
From: Edward Nolan <eddiejnolan@gmail.com>
Date: Sun, 26 Apr 2026 22:39:13 -0400
Subject: [PATCH] Update flag forking approach to use split config.hpp and
 config_generated.hpp files

This commit reflects the new flag forking approach discussed in the
most recent Beman weekly sync:

- For any configuration option where a compiler flag could cause
  differences in behavior that lead to ODR issues when linking two
  artifacts generated with different flags, maintainers generate a
  compiler definition like BEMAN_EXEMPLAR_FOOBAR into a
  config_generated.hpp header from a config_generated.hpp.in template.
- Separately, a config.hpp file contains defaults for each
  definition. These defaults are only enabled if __has_include shows
  that the config_generated.hpp file is not present.
---
 CMakeLists.txt                                       |  4 ++--
 include/beman/inplace_vector/CMakeLists.txt          |  5 ++++-
 include/beman/inplace_vector/config.hpp              | 11 +++++++++++
 include/beman/inplace_vector/config.hpp.in           |  6 ------
 include/beman/inplace_vector/config_generated.hpp.in |  6 ++++++
 include/beman/inplace_vector/inplace_vector.hpp      |  6 ------
 6 files changed, 23 insertions(+), 15 deletions(-)
 create mode 100644 include/beman/inplace_vector/config.hpp
 delete mode 100644 include/beman/inplace_vector/config.hpp.in
 create mode 100644 include/beman/inplace_vector/config_generated.hpp.in

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8858de2..7594fa2 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -31,8 +31,8 @@ option(
 )
 
 configure_file(
-    "${PROJECT_SOURCE_DIR}/include/beman/inplace_vector/config.hpp.in"
-    "${PROJECT_BINARY_DIR}/include/beman/inplace_vector/config.hpp"
+    "${PROJECT_SOURCE_DIR}/include/beman/inplace_vector/config_generated.hpp.in"
+    "${PROJECT_BINARY_DIR}/include/beman/inplace_vector/config_generated.hpp"
     @ONLY
 )
 
diff --git a/include/beman/inplace_vector/CMakeLists.txt b/include/beman/inplace_vector/CMakeLists.txt
index 9a20b6a..10cd0fb 100644
--- a/include/beman/inplace_vector/CMakeLists.txt
+++ b/include/beman/inplace_vector/CMakeLists.txt
@@ -4,5 +4,8 @@ target_sources(
     beman.inplace_vector
     PUBLIC
         FILE_SET HEADERS
-            FILES inplace_vector.hpp "${CMAKE_CURRENT_BINARY_DIR}/config.hpp"
+            FILES
+                inplace_vector.hpp
+                config.hpp
+                "${CMAKE_CURRENT_BINARY_DIR}/config_generated.hpp"
 )
diff --git a/include/beman/inplace_vector/config.hpp b/include/beman/inplace_vector/config.hpp
new file mode 100644
index 0000000..e696fa3
--- /dev/null
+++ b/include/beman/inplace_vector/config.hpp
@@ -0,0 +1,11 @@
+#ifndef BEMAN_INPLACE_VECTOR_CONFIG_HPP
+#define BEMAN_INPLACE_VECTOR_CONFIG_HPP
+
+#if !defined(__has_include) ||                                                 \
+    __has_include(<beman/inplace_vector/config_generated.hpp>)
+#include <beman/inplace_vector/config_generated.hpp>
+#else
+#define BEMAN_INPLACE_VECTOR_NO_EXCEPTIONS() 0
+#endif
+
+#endif
diff --git a/include/beman/inplace_vector/config.hpp.in b/include/beman/inplace_vector/config.hpp.in
deleted file mode 100644
index b551164..0000000
--- a/include/beman/inplace_vector/config.hpp.in
+++ /dev/null
@@ -1,6 +0,0 @@
-#ifndef BEMAN_INPLACE_VECTOR_CONFIG_HPP
-#define BEMAN_INPLACE_VECTOR_CONFIG_HPP
-
-#cmakedefine01 BEMAN_INPLACE_VECTOR_NO_EXCEPTIONS()
-
-#endif
diff --git a/include/beman/inplace_vector/config_generated.hpp.in b/include/beman/inplace_vector/config_generated.hpp.in
new file mode 100644
index 0000000..b2c8e25
--- /dev/null
+++ b/include/beman/inplace_vector/config_generated.hpp.in
@@ -0,0 +1,6 @@
+#ifndef BEMAN_INPLACE_VECTOR_CONFIG_GENERATED_HPP
+#define BEMAN_INPLACE_VECTOR_CONFIG_GENERATED_HPP
+
+#cmakedefine01 BEMAN_INPLACE_VECTOR_NO_EXCEPTIONS()
+
+#endif
diff --git a/include/beman/inplace_vector/inplace_vector.hpp b/include/beman/inplace_vector/inplace_vector.hpp
index 4395f45..dfd004f 100644
--- a/include/beman/inplace_vector/inplace_vector.hpp
+++ b/include/beman/inplace_vector/inplace_vector.hpp
@@ -3,9 +3,7 @@
 #ifndef BEMAN_INPLACE_VECTOR_INPLACE_VECTOR_HPP
 #define BEMAN_INPLACE_VECTOR_INPLACE_VECTOR_HPP
 
-#if !defined(__has_include) || __has_include(<beman/inplace_vector/config.hpp>)
 #include <beman/inplace_vector/config.hpp>
-#endif
 
 #include <algorithm> // for rotate...
 #include <array>
@@ -24,10 +22,6 @@
 
 #ifndef BEMAN_IV_THROW_OR_ABORT
 
-#ifndef BEMAN_INPLACE_VECTOR_NO_EXCEPTIONS
-#define BEMAN_INPLACE_VECTOR_NO_EXCEPTIONS() 0
-#endif
-
 #if BEMAN_INPLACE_VECTOR_NO_EXCEPTIONS()
 #include <cstdlib> // for abort
 #define BEMAN_IV_THROW_OR_ABORT(x) abort()