Fix out-of-bounds error in pyroot

 526/1416 Test   root-project#63: pyunittests-bindings-pyroot-pythonizations-pyroot-pyz-tf-pycallables ..........................***Failed   75.51 sec
test_callable (tf_pycallables.TF1.test_callable)
Test function provided as callable ... /usr/include/c++/15/bits/stl_bvector.h:1134: std::vector<bool, _Alloc>::reference std::vector<bool, _Alloc>::operator[](size_type) [with _Alloc = std::allocator<bool>; reference = std::vector<bool>::reference; size_type = long unsigned int]: Assertion '__n < this->size()' failed.
 *** Break *** abort

===========================================================
The lines below might hint at the cause of the crash. If you see question
marks as part of the stack trace, try to recompile with debugging information
enabled and export CLING_DEBUG=1 environment variable before running.
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that might help us fixing this issue.
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 #10 0x00007f6bcac7fea4 in __pthread_kill_implementation () from /lib64/libc.so.6
 #11 0x00007f6bcac264de in raise () from /lib64/libc.so.6
 #12 0x00007f6bcac0e350 in abort () from /lib64/libc.so.6
 #13 0x00007f6bc9a0be02 in std::__glibcxx_assert_fail(char const*, int, char const*, char const*) () from /lib64/libstdc++.so.6
 #14 0x00007f6bb9b15257 in std::vector<bool, std::allocator<bool> >::operator[](unsigned long) [clone .part.0] [clone .lto_priv.0] (__n=<optimized out>, this=<optimized out>) at /usr/include/c++/15/bits/stl_bvector.h:1134
 #15 0x00007f6bb9bab976 in std::vector<bool, std::allocator<bool> >::operator[] (this=<synthetic pointer>, __n=0) at /usr/include/c++/15/bits/stl_bvector.h:201
 #16 CPyCppyy::Utility::ConstructCallbackPreamble (retType="Double_t", argtypes=..., code=Python Exception <class 'IndexError'>: list index out of range
 #17 0x00007f6bb9b389e0 in PyFunction_AsCPointer (pyobject=<optimized out>, pyobject
entry=0x7f6bb8f838c0, rettype="Double_t", signature="(Double_t*,Double_t*)") at /builddir/build/BUILD/root-6.34.02-build/root-6.34.02/bindings/pyroot/cppyy/CPyCppyy/src/Converters.cxx:2713
 #18 0x00007f6bb9b39851 in CPyCppyy::(anonymous namespace)::FunctionPointerConverter::SetArg (this=0x55eb25d61d40, pyobject=0x7f6bb8f838c0, para=..., ctxt=0x7ffc484855c0) at /builddir/build/BUILD/root-6.34.02-build/root-6.34.02/bindings/pyroot/cppyy/CPyCppyy/src/Converters.cxx:2768

Author: ellert

bindings/pyroot/cppyy/CPyCppyy/src/Utility.cxx

@@ -645,7 +645,7 @@ void CPyCppyy::Utility::ConstructCallbackPreamble(const std::string& retType,
              << retType << "\"), CPyCppyy::DestroyConverter};\n";
     std::vector<bool> arg_is_ptr;
     if (nArgs) {
-        arg_is_ptr.reserve(nArgs);
+        arg_is_ptr.resize(nArgs);
         code << "    CPYCPPYY_STATIC std::vector<std::unique_ptr<CPyCppyy::Converter, std::function<void(CPyCppyy::Converter*)>>> argcvs;\n"
              << "    if (argcvs.empty()) {\n"
              << "      argcvs.reserve(" << nArgs << ");\n";