From b743e586aebcff74c8e74b7e649aaf1f38a4efe3 Mon Sep 17 00:00:00 2001
From: Mike Taves <mwtoews@gmail.com>
Date: Sat, 5 Sep 2026 14:27:05 +1200
Subject: [PATCH] Fix 32-bit GCC 13 and later excess precision

---
 CMakeLists.txt              | 8 +++++++-
 ci/linux_gcc_32bit/start.sh | 2 +-
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index fe447e9a70..b9b7e8cfd9 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -131,7 +131,13 @@ if (CMAKE_CXX_COMPILER_ID STREQUAL "IntelLLVM")
   # breaks std::isinf(), std::isnan(), etc.
   string(APPEND CMAKE_C_FLAGS " -fno-fast-math")
   string(APPEND CMAKE_CXX_FLAGS " -fno-fast-math")
-endif ()
+elseif(CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND
+       CMAKE_CXX_COMPILER_VERSION VERSION_GREATER_EQUAL 13 AND
+       CMAKE_SIZEOF_VOID_P EQUAL 4)
+  # GCC 13 and later changed their C++ excess precision support, which impacts
+  # 32-bit builds. This restores the previous behavior.
+  string(APPEND CMAKE_CXX_FLAGS " -fexcess-precision=fast")
+endif()
 
 # Add other supported compiler flags
 if(("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU") OR ("${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang"))
diff --git a/ci/linux_gcc_32bit/start.sh b/ci/linux_gcc_32bit/start.sh
index 7b13e58473..2fc007c6a2 100755
--- a/ci/linux_gcc_32bit/start.sh
+++ b/ci/linux_gcc_32bit/start.sh
@@ -6,7 +6,7 @@ export TRAVIS_OS_NAME=linux
 export BUILD_NAME=linux_gcc_32bit
 export TRAVIS_BUILD_DIR="$WORK_DIR"
 
-GCC_VERSION=12
+GCC_VERSION=13
 
 ARCH=i386