spack/var/spack/repos/builtin/packages/neuron/patch-v782-git-cmake-avx512.patch

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 391d4daa..20b8b571 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -98,7 +98,7 @@ Currently we have enabled CMake code formatting using [cmake-format](https://git
 * Make sure to install cmake-format utility with Python version you are using:
 
 ```
-pip3.7 install cmake-format==0.6.0 --user
+pip3.7 install cmake-format==0.6.0 pyyaml --user
 ```
 Now you should have `cmake-format` command available.
 
diff --git a/cmake/ExternalProjectHelper.cmake b/cmake/ExternalProjectHelper.cmake
index 57094e7e..eeb6dfc2 100644
--- a/cmake/ExternalProjectHelper.cmake
+++ b/cmake/ExternalProjectHelper.cmake
@@ -1,5 +1,15 @@
 find_package(Git QUIET)
 
+if(${GIT_FOUND} AND EXISTS ${CMAKE_SOURCE_DIR}/.git)
+  execute_process(
+    COMMAND ${GIT_EXECUTABLE} --git-dir=.git describe --all
+    RESULT_VARIABLE NOT_A_GIT_REPO
+    ERROR_QUIET
+    WORKING_DIRECTORY ${PROJECT_SOURCE_DIR})
+else()
+  set(NOT_A_GIT_REPO "NotAGitRepo")
+endif()
+
 # initialize submodule with given path
 function(initialize_submodule path)
   if(NOT ${GIT_FOUND})
@@ -9,7 +19,7 @@ function(initialize_submodule path)
   message(STATUS "Sub-module : missing ${path} : running git submodule update --init --recursive")
   execute_process(
     COMMAND
-      git submodule update --init --recursive -- ${path}
+      ${GIT_EXECUTABLE}  submodule update --init --recursive -- ${path}
     WORKING_DIRECTORY ${PROJECT_SOURCE_DIR})
 endfunction()
 
@@ -20,6 +30,9 @@ function(add_external_project name)
     NAMES CMakeLists.txt
     PATHS "${PROJECT_SOURCE_DIR}/external/${name}")
   if(NOT EXISTS ${${name}_PATH})
+    if(NOT_A_GIT_REPO)
+      message(FATAL_ERROR "Looks like you are building from source. Git needed for ${name} feature.")
+    endif()
     initialize_submodule(external/${name})
   else()
     message(STATUS "Sub-project : using ${name} from from external/${name}")
diff --git a/git2nrnversion_h.sh b/git2nrnversion_h.sh
index d62b7410..4d8e4015 100755
--- a/git2nrnversion_h.sh
+++ b/git2nrnversion_h.sh
@@ -20,10 +20,9 @@ if git log > /dev/null && test -d .git ; then
 elif test -f src/nrnoc/nrnversion.h ; then
         sed -n '1,$p' src/nrnoc/nrnversion.h
 else
-        echo "#define GIT_DATE \"1999-12-31\""
-        echo "#define GIT_BRANCH \"?\""
-        echo "#define GIT_CHANGESET \"?\""
-        echo "#define GIT_DESCRIBE \"?\""
-        exit 1
+        echo "#define GIT_DATE \"Build Time: $(date "+%Y-%m-%d-%H:%M:%S")\""
+        echo "#define GIT_BRANCH \"unknown branch\""
+        echo "#define GIT_CHANGESET \"unknown commit id\""
+        echo "#define GIT_DESCRIBE \"${PROJECT_VERSION}.dev0\""
 fi
 
diff --git a/src/ivoc/ivocvect.cpp b/src/ivoc/ivocvect.cpp
index 4884614a..4da9e17e 100644
--- a/src/ivoc/ivocvect.cpp
+++ b/src/ivoc/ivocvect.cpp
@@ -67,7 +67,26 @@ extern "C" {
 #define FRead(arg1,arg2,arg3,arg4) if (fread(arg1,arg2,arg3,arg4) != arg3) {}
 #endif
 
-static double dmaxint_;
+/**
+ * As all parameters are passed from hoc as double, we need
+ * to calculate max integer that can fit into double variable.
+ *
+ * With IEEE 64-bit double has 52 bits of mantissa, so it's 2^53.
+ * calculating it with approach `while (dbl + 1 != dbl) dbl++;`
+ * has issues with SSE and other 32 bits platform. So we are using
+ * direct value here.
+ *
+ * The maximum mantissa 0xFFFFFFFFFFFFF which is 52 bits all 1.
+ * In Python it's:
+ *
+ *  >>> (2.**53).hex()
+ *   '0x1.0000000000000p+53'
+ *  >>> (2.**53)
+ *   9007199254740992.0
+ *
+ * See https://stackoverflow.com/questions/1848700/biggest-integer-that-can-be-stored-in-a-double
+ */
+static double dmaxint_ = 9007199254740992;
 
 // Definitions allow machine independent write and read
 // note that must include BYTEHEADER at head of routine
@@ -3776,20 +3795,7 @@ static void steer_x(void* v) {
 }
 
 void Vector_reg() {
-	dmaxint_ = 1073741824.;
-	for(;;) {
-		if (dmaxint_*2. == double(int(dmaxint_*2.))) {
-			dmaxint_ *= 2.;
-		}else{
-			if (dmaxint_*2. - 1. == double(int(dmaxint_*2. - 1.))) {
-				dmaxint_ = 2.*dmaxint_ - 1.;
-			}
-			break;
-		}
-	}		
-	//printf("dmaxint=%30.20g   %d\n", dmaxint_, (long)dmaxint_);
-        class2oc("Vector", v_cons, v_destruct, v_members, NULL, v_retobj_members,
-        	v_retstr_members);
+	class2oc("Vector", v_cons, v_destruct, v_members, NULL, v_retobj_members, v_retstr_members);
 	svec_ = hoc_lookup("Vector");
 	// now make the x variable an actual double
 	Symbol* sv = hoc_lookup("Vector");
diff --git a/src/nrniv/CMakeLists.txt b/src/nrniv/CMakeLists.txt
index 30024d6e..26f76a98 100644
--- a/src/nrniv/CMakeLists.txt
+++ b/src/nrniv/CMakeLists.txt
@@ -139,7 +139,8 @@ set(NRN_INCLUDE_DIRS
 # is different from the contents of nrnversion.h
 # ~~~
 add_custom_target(
-  nrnversion_h ${PROJECT_SOURCE_DIR}/git2nrnversion_h.sh ${PROJECT_SOURCE_DIR} > nrnversion.h.tmp
+  nrnversion_h
+  COMMAND ${CMAKE_COMMAND} -E env PROJECT_VERSION=${PROJECT_VERSION} $ENV{SHELL} ${PROJECT_SOURCE_DIR}/git2nrnversion_h.sh ${PROJECT_SOURCE_DIR} > nrnversion.h.tmp
   COMMAND ${CMAKE_COMMAND} -E copy_if_different nrnversion.h.tmp ${NRN_NRNOC_SRC_DIR}/nrnversion.h
   DEPENDS ${PROJECT_SOURCE_DIR}/git2nrnversion_h.sh)