diff --git a/build/make.mingw64.lib.py b/build/make.mingw64.lib.py
index f386449..c6ea7d7 100644
--- a/build/make.mingw64.lib.py
+++ b/build/make.mingw64.lib.py
@@ -16,7 +16,7 @@ builddir = "./build_mingw64"
 
 doinstall = True   #copies the build_output to the install dir when finished
 cc = "x86_64-w64-mingw32-g++" #compiler
-cflags = "-fPIC -O3 -std=c++17"
+cflags = "-fPIC -O3"
 libraries = "-l{}".format(libname)
 libdirs = "-L{} -L{}/lib -L{}/lib".format(builddir,commondir,depdir)
 linkerflags = "-static -static-libgcc -Wl,-rpath=."
diff --git a/build/make.mingw64.test.py b/build/make.mingw64.test.py
index bcdd319..e333aa1 100644
--- a/build/make.mingw64.test.py
+++ b/build/make.mingw64.test.py
@@ -16,7 +16,7 @@ builddir = "./build_mingw64"
 
 doinstall = False   #copies the build_output to the install dir when finished
 cc = "x86_64-w64-mingw32-g++" #compiler
-cflags = "-fPIC -O3 -std=c++17"
+cflags = "-fPIC -O3"
 libraries = "-l{}".format(libname)
 libdirs = "-L{} -L{}/lib -L{}/lib".format(builddir,commondir,depdir)
 linkerflags = "-static -static-libgcc -Wl,-rpath=."
diff --git a/build_linux64/objstore/amscpptemplate25a_src2.o b/build_linux64/objstore/amscpptemplate25a_src2.o
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diff --git a/build_linux64/objstore/amscpptemplate25a_template.o b/build_linux64/objstore/amscpptemplate25a_template.o
deleted file mode 100644
index 06d6ac8..0000000
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diff --git a/build_linux64/objstore/amsmathtuil25_test1.o b/build_linux64/objstore/amsmathtuil25_test1.o
deleted file mode 100644
index 1b3dc46..0000000
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diff --git a/build_linux64/objstore/amsmathutiil25_random.o b/build_linux64/objstore/amsmathutiil25_random.o
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diff --git a/build_linux64/objstore/amsmathutil25_amsarray.o b/build_linux64/objstore/amsmathutil25_amsarray.o
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diff --git a/build_linux64/objstore/amsmathutil25_amsarray_sort.o b/build_linux64/objstore/amsmathutil25_amsarray_sort.o
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index f1167cf..0000000
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diff --git a/build_linux64/objstore/amsmathutil25_mathfns1.o b/build_linux64/objstore/amsmathutil25_mathfns1.o
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index 0e62279..0000000
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diff --git a/build_linux64/objstore/amsmathutil25_utils1.o b/build_linux64/objstore/amsmathutil25_utils1.o
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index 3f6b99e..0000000
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deleted file mode 100644
index f6a6e54..0000000
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diff --git a/build_linux64/objstore/amsmathutil25_vec2f.o b/build_linux64/objstore/amsmathutil25_vec2f.o
deleted file mode 100644
index 43b9398..0000000
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diff --git a/build_linux64/objstore/amsmathutil25_vec3.o b/build_linux64/objstore/amsmathutil25_vec3.o
deleted file mode 100644
index 903d5f2..0000000
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diff --git a/build_linux64/objstore/amsmathutil25_vec3f.o b/build_linux64/objstore/amsmathutil25_vec3f.o
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diff --git a/build_linux64/objstore/amsmathutil25_vec4.o b/build_linux64/objstore/amsmathutil25_vec4.o
deleted file mode 100644
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diff --git a/build_linux64/objstore/amsmathutil25_vec4f.o b/build_linux64/objstore/amsmathutil25_vec4f.o
deleted file mode 100644
index dc12f7c..0000000
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diff --git a/build_linux64/objstore/amsmathutil2t_complex128.o b/build_linux64/objstore/amsmathutil2t_complex128.o
deleted file mode 100644
index fdae151..0000000
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diff --git a/build_linux64/objstore/amsmathutil2t_complex64.o b/build_linux64/objstore/amsmathutil2t_complex64.o
deleted file mode 100644
index 866300f..0000000
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diff --git a/build_mingw64/tests.exe b/build_mingw64/tests.exe
index 1fbc977..e873bd2 100644
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diff --git a/include/amsmathutil25/util/amsmathutil25_utilimpl.hpp b/include/amsmathutil25/util/amsmathutil25_utilimpl.hpp
index 0bce248..c9bcedf 100644
--- a/include/amsmathutil25/util/amsmathutil25_utilimpl.hpp
+++ b/include/amsmathutil25/util/amsmathutil25_utilimpl.hpp
@@ -18,12 +18,16 @@ template<typename callable, typename ... argst> int threaded_execute(callable &&
     {
         nthreads = 1;
         I = 0;
-        std::invoke(
-            std::forward<callable>(fptr),
-            I,
-            nthreads,
-            std::forward<argst>(args)...
-        );
+        // std::invoke(
+        //     std::forward<callable>(fptr),
+        //     I,
+        //     nthreads,
+        //     std::forward<argst>(args)...
+        // );
+
+        //std::invoke is a C++17 feature, and mingw8 complains even so.
+        // Can I get away with just calling the functions?
+        fptr(I,nthreads,std::forward<argst>(args)...);
     }
     else
     {