cpython/Tools/c-analyzer/c_parser/preprocessor/gcc.py
Eric Snow 345cd37abe
bpo-36876: Fix the C analyzer tool. (GH-22841)
The original tool wasn't working right and it was simpler to create a new one, partially re-using some of the old code. At this point the tool runs properly on the master. (Try: ./python Tools/c-analyzer/c-analyzer.py analyze.)  It take ~40 seconds on my machine to analyze the full CPython code base.

Note that we'll need to iron out some OS-specific stuff (e.g. preprocessor). We're okay though since this tool isn't used yet in our workflow. We will also need to verify the analysis results in detail before activating the check in CI, though I'm pretty sure it's close.

https://bugs.python.org/issue36876
2020-10-22 18:42:51 -06:00

123 lines
3.1 KiB
Python

import os.path
import re
from . import common as _common
TOOL = 'gcc'
# https://gcc.gnu.org/onlinedocs/cpp/Preprocessor-Output.html
LINE_MARKER_RE = re.compile(r'^# (\d+) "([^"]+)"(?: [1234])*$')
PREPROC_DIRECTIVE_RE = re.compile(r'^\s*#\s*(\w+)\b.*')
COMPILER_DIRECTIVE_RE = re.compile(r'''
^
(.*?) # <before>
(__\w+__) # <directive>
\s*
[(] [(]
(
[^()]*
(?:
[(]
[^()]*
[)]
[^()]*
)*
) # <args>
( [)] [)] )? # <closed>
''', re.VERBOSE)
POST_ARGS = (
'-pthread',
'-std=c99',
#'-g',
#'-Og',
#'-Wno-unused-result',
#'-Wsign-compare',
#'-Wall',
#'-Wextra',
'-E',
)
def preprocess(filename, incldirs=None, macros=None, samefiles=None):
text = _common.preprocess(
TOOL,
filename,
incldirs=incldirs,
macros=macros,
#preargs=PRE_ARGS,
postargs=POST_ARGS,
executable=['gcc'],
compiler='unix',
)
return _iter_lines(text, filename, samefiles)
def _iter_lines(text, filename, samefiles, *, raw=False):
lines = iter(text.splitlines())
# Build the lines and filter out directives.
partial = 0 # depth
origfile = None
for line in lines:
m = LINE_MARKER_RE.match(line)
if m:
lno, origfile = m.groups()
lno = int(lno)
elif _filter_orig_file(origfile, filename, samefiles):
if (m := PREPROC_DIRECTIVE_RE.match(line)):
name, = m.groups()
if name != 'pragma':
raise Exception(line)
else:
if not raw:
line, partial = _strip_directives(line, partial=partial)
yield _common.SourceLine(
_common.FileInfo(filename, lno),
'source',
line or '',
None,
)
lno += 1
def _strip_directives(line, partial=0):
# We assume there are no string literals with parens in directive bodies.
while partial > 0:
if not (m := re.match(r'[^{}]*([()])', line)):
return None, partial
delim, = m.groups()
partial += 1 if delim == '(' else -1 # opened/closed
line = line[m.end():]
line = re.sub(r'__extension__', '', line)
while (m := COMPILER_DIRECTIVE_RE.match(line)):
before, _, _, closed = m.groups()
if closed:
line = f'{before} {line[m.end():]}'
else:
after, partial = _strip_directives(line[m.end():], 2)
line = f'{before} {after or ""}'
if partial:
break
return line, partial
def _filter_orig_file(origfile, current, samefiles):
if origfile == current:
return True
if origfile == '<stdin>':
return True
if os.path.isabs(origfile):
return False
for filename in samefiles or ():
if filename.endswith(os.path.sep):
filename += os.path.basename(current)
if origfile == filename:
return True
return False