Only generate the version & build info once.

Author: ericsnowcurrently

Include/internal/pycore_pylifecycle.h

@@ -33,6 +33,7 @@ PyAPI_FUNC(int) _Py_IsLocaleCoercionTarget(const char *ctype_loc);
 
 /* Various one-time initializers */
 
+extern void _Py_InitVersion(void);
 extern PyStatus _PyImport_Init(void);
 extern PyStatus _PyFaulthandler_Init(int enable);
 extern int _PyTraceMalloc_Init(int enable);

Modules/getbuildinfo.c

@@ -31,12 +31,18 @@
 #define GITBRANCH ""
 #endif
 
+static int initialized = 0;
+static char buildinfo[50 + sizeof(GITVERSION) +
+                      ((sizeof(GITTAG) > sizeof(GITBRANCH)) ?
+                       sizeof(GITTAG) : sizeof(GITBRANCH))];
+
 const char *
 Py_GetBuildInfo(void)
 {
-    static char buildinfo[50 + sizeof(GITVERSION) +
-                          ((sizeof(GITTAG) > sizeof(GITBRANCH)) ?
-                           sizeof(GITTAG) : sizeof(GITBRANCH))];
+    if (initialized) {
+        return buildinfo;
+    }
+    initialized = 1;
     const char *revision = _Py_gitversion();
     const char *sep = *revision ? ":" : "";
     const char *gitid = _Py_gitidentifier();

Python/getversion.c

@@ -5,12 +5,23 @@
 
 #include "patchlevel.h"
 
-const char *
-Py_GetVersion(void)
+static int initialized = 0;
+static char version[250];
+
+void _Py_InitVersion(void)
 {
-    static char version[250];
+    if (initialized) {
+        return;
+    }
+    initialized = 1;
     PyOS_snprintf(version, sizeof(version), "%.80s (%.80s) %.80s",
                   PY_VERSION, Py_GetBuildInfo(), Py_GetCompiler());
+}
+
+const char *
+Py_GetVersion(void)
+{
+    _Py_InitVersion();
     return version;
 }
 

Python/pylifecycle.c

@@ -600,6 +600,8 @@ pycore_init_runtime(_PyRuntimeState *runtime,
      */
     _PyRuntimeState_SetFinalizing(runtime, NULL);
 
+    _Py_InitVersion();
+
     status = _Py_HashRandomization_Init(config);
     if (_PyStatus_EXCEPTION(status)) {
         return status;

Tools/c-analyzer/cpython/globals-to-fix.tsv

@@ -333,7 +333,6 @@ Python/dtoa.c	-	freelist	-
 Python/dtoa.c	-	private_mem	-
 
 # local buffer
-Python/getversion.c	Py_GetVersion	version	-
 Python/suggestions.c	levenshtein_distance	buffer	-
 
 # linked list

Tools/c-analyzer/cpython/ignored.tsv

@@ -40,6 +40,8 @@ Python/import.c	-	PyImport_Inittab	-
 #-----------------------
 # effectively const, initialized during init
 
+Modules/getbuildinfo.c	-	buildinfo	-
+Modules/getbuildinfo.c	-	initialized	-
 Objects/floatobject.c	-	double_format	-
 Objects/floatobject.c	-	float_format	-
 Objects/unicodeobject.c	-	bloom_linebreak	-
@@ -48,6 +50,8 @@ Python/bootstrap_hash.c	-	_Py_HashSecret_Initialized	-
 Python/fileutils.c	-	_Py_open_cloexec_works	-
 Python/fileutils.c	-	force_ascii	-
 Python/fileutils.c	set_inheritable	ioctl_works	-
+Python/getversion.c	-	initialized	-
+Python/getversion.c	-	version	-
 Python/import.c	import_find_and_load	header	-
 Python/initconfig.c	-	orig_argv	-
 Python/preconfig.c	-	Py_FileSystemDefaultEncoding	-
@@ -98,8 +102,6 @@ Python/pathconfig.c	-	_Py_path_config	-
 # XXX The analyzer should have ignored these.
 Modules/_io/_iomodule.c	-	_PyIO_Module	-
 Modules/_sqlite/module.c	-	_sqlite3module	-
-# a pre-allocated buffer with a very unlikely race
-Modules/getbuildinfo.c	Py_GetBuildInfo	buildinfo	-
 
 
 ##################################