Overhauld 'check_config_h()': now returns a (status, details) tuple,
and is much better documented to boot.
diff --git a/Lib/distutils/cygwinccompiler.py b/Lib/distutils/cygwinccompiler.py
index da0d60b..2ac2678 100644
--- a/Lib/distutils/cygwinccompiler.py
+++ b/Lib/distutils/cygwinccompiler.py
@@ -65,11 +65,13 @@
UnixCCompiler.__init__ (self, verbose, dry_run, force)
- check_result = check_config_h()
- self.debug_print("Python's GCC status: %s" % check_result)
- if check_result[:2] <> "OK":
+ (status, details) = check_config_h()
+ self.debug_print("Python's GCC status: %s (details: %s)" %
+ (status, details))
+ if status is not CONFIG_H_OK:
self.warn(
- "Python's config.h doesn't seem to support your compiler. "
+ "Python's config.h doesn't seem to support your compiler. " +
+ ("Reason: %s." % details) +
"Compiling may fail because of undefined preprocessor macros.")
(self.gcc_version, self.ld_version, self.dllwrap_version) = \
@@ -241,43 +243,60 @@
# default, we should at least warn the user if he is using a unmodified
# version.
+CONFIG_H_OK = "ok"
+CONFIG_H_NOTOK = "not ok"
+CONFIG_H_UNCERTAIN = "uncertain"
+
def check_config_h():
- """Checks if the GCC compiler is mentioned in config.h. If it is not,
- compiling probably doesn't work.
+
+ """Check if the current Python installation (specifically, config.h)
+ appears amenable to building extensions with GCC. Returns a tuple
+ (status, details), where 'status' is one of the following constants:
+ CONFIG_H_OK
+ all is well, go ahead and compile
+ CONFIG_H_NOTOK
+ doesn't look good
+ CONFIG_H_UNCERTAIN
+ not sure -- unable to read config.h
+ 'details' is a human-readable string explaining the situation.
+
+ Note there are two ways to conclude "OK": either 'sys.version' contains
+ the string "GCC" (implying that this Python was built with GCC), or the
+ installed "config.h" contains the string "__GNUC__".
"""
- # return values
- # "OK, python was compiled with GCC"
- # "OK, python's config.h mentions __GCC__"
- # "uncertain, because we couldn't check it"
- # "not OK, because we didn't found __GCC__ in config.h"
- # You could check check_config_h()[:2] == "OK"
+
+ # XXX since this function also checks sys.version, it's not strictly a
+ # "config.h" check -- should probably be renamed...
from distutils import sysconfig
import string,sys
# if sys.version contains GCC then python was compiled with
# GCC, and the config.h file should be OK
- if -1 == string.find(sys.version,"GCC"):
- pass # go to the next test
- else:
- return "OK, python was compiled with GCC"
+ if string.find(sys.version,"GCC") >= 0:
+ return (CONFIG_H_OK, "sys.version mentions 'GCC'")
+ fn = sysconfig.get_config_h_filename()
try:
# It would probably better to read single lines to search.
# But we do this only once, and it is fast enough
- f=open(sysconfig.get_config_h_filename())
- s=f.read()
+ f = open(fn)
+ s = f.read()
f.close()
- # is somewhere a #ifdef __GNUC__ or something similar
- if -1 == string.find(s,"__GNUC__"):
- return "not OK, because we didn't found __GCC__ in config.h"
- else:
- return "OK, python's config.h mentions __GCC__"
- except IOError:
+ except IOError, exc:
# if we can't read this file, we cannot say it is wrong
# the compiler will complain later about this file as missing
- pass
- return "uncertain, because we couldn't check it"
+ return (CONFIG_H_UNCERTAIN,
+ "couldn't read '%s': %s" % (fn, exc.strerror))
+
+ else:
+ # "config.h" contains an "#ifdef __GNUC__" or something similar
+ if string.find(s,"__GNUC__") >= 0:
+ return (CONFIG_H_OK, "'%s' mentions '__GNUC__'" % fn)
+ else:
+ return (CONFIG_H_NOTOK, "'%s' does not mention '__GNUC__'" % fn)
+
+
def get_versions():
""" Try to find out the versions of gcc, ld and dllwrap.