diff --git a/cmake.patch b/cmake.patch
index 6e5a113..1a767a1 100644
--- a/cmake.patch
+++ b/cmake.patch
@@ -10,3 +10,16 @@ index 9d14f6b70f..491f023493 100644
  #include <functional>
  #include <memory>
  
+
+--- cmake.orig/Source/cmake.cxx
++++ cmake/Source/cmake.cxx
+@@ -131,7 +131,9 @@
+ // NOTE: the __linux__ macro is predefined on Android host too, but
+ // main CMakeLists.txt filters out this generator by host name.
+ #if (defined(__linux__) && !defined(__ANDROID__)) || defined(_WIN32)
++#if !defined(CMAKE_BOOTSTRAP)
+ #  include "cmGlobalGhsMultiGenerator.h"
++#endif
+ #endif
+ 
+ #if defined(__APPLE__)
diff --git a/swift-lang.spec b/swift-lang.spec
index b24bf79..92beeef 100644
--- a/swift-lang.spec
+++ b/swift-lang.spec
@@ -361,6 +361,10 @@ cp %{SOURCE100} swift/utils/fedora-presets.ini
 %build
 export VERBOSE=1
 
+# Workaround for GCC 16 ICE in cmath / riemann_zeta
+export CFLAGS="-O2 -g -fno-builtin-logf"
+export CXXFLAGS="-O2 -g -fno-builtin-logf"
+
 # Four-stage bootstrap to build Swift from scratch without external Swift compiler
 # Stage 0: Build minimal Swift toolchain from C++ using gold linker
 #          Produces: Swift compiler with C++ legacy driver (no SwiftPM, no swift-driver)