hanchenye-llvm-project/clang
Reid Kleckner b2da086103 Push a function scope when parsing function bodies without a declaration
Summary:
This is PR36536.

There are a few ways to reach Sema::ActOnStartOfFunctionDef with a null
Decl. Currently, the parser continues on to attempt to parse the
statements in the function body without pushing a function scope or
declaration context. However, lots of statement parsing logic relies on
getCurFunction() returning something reasonable. It turns out that
getCurFunction() will never return null today because of an optimization
where Sema pre-allocates one FunctionScopeInfo and reuses it when
possible. This goes wrong when something inside the function body causes
us to push another function scope, such as requiring an implicit
definition of a special member function. Reusing the state clears it
out, which will lead to bugs. In PR36536, we found that the SwitchStack
gets unbalanced, because we push a switch, clear out the stack, and then
try to pop a switch that isn't there.

As a follow-up, I plan to move the pre-allocated FunctionScopeInfo out
of the FunctionScopes stack. This means the FunctionScopes stack will
often be empty, and callers of getCurFunction() will need to check for
null.

Reviewers: thakis

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D43980

llvm-svn: 326926
2018-03-07 18:55:10 +00:00
..
INPUTS
bindings Remove duplicate python libclang changes from r320748 2017-12-14 23:40:42 +00:00
cmake [Fuchsia] Include libClang and clang-include-fixer in the toolchain 2018-02-21 04:39:15 +00:00
docs Add Clang ReleaseNotes that --autocomplete breaks backward compatibily 2018-03-07 11:34:02 +00:00
examples [analyzer] introduce getSVal(Stmt *) helper on ExplodedNode, make sure the helper is used consistently 2018-01-17 20:27:29 +00:00
include [ASTMatcher] Extend hasAnyArgument to ObjCMessageExpr 2018-03-07 02:32:44 +00:00
lib Push a function scope when parsing function bodies without a declaration 2018-03-07 18:55:10 +00:00
runtime [clang] Use add_llvm_install_targets 2017-11-30 22:35:02 +00:00
test Push a function scope when parsing function bodies without a declaration 2018-03-07 18:55:10 +00:00
tools Resubmit [analyzer] Support for naive cross translation unit analysis 2018-03-01 14:54:16 +00:00
unittests [ASTMatcher] Extend hasAnyArgument to ObjCMessageExpr 2018-03-07 02:32:44 +00:00
utils Revert r326602, it caused PR36620. 2018-03-07 02:22:41 +00:00
www [www] Capitalize "Clang" when referring to the project, and generalize the 2018-03-01 22:01:06 +00:00
.arcconfig [clang] Set up .arcconfig to point to new Diffusion C repository 2017-11-27 17:21:24 +00:00
.clang-format
.clang-tidy
.gitignore
CMakeLists.txt [FrontEnd] Allow overriding the default C/C++ -std via CMake vars 2018-03-06 21:26:28 +00:00
CODE_OWNERS.TXT Change code owner for Clang Static Analyzer to Devin Coughlin. 2017-11-17 23:19:04 +00:00
INSTALL.txt
LICENSE.TXT
ModuleInfo.txt
NOTES.txt
README.txt Test commit 2017-10-21 16:03:17 +00:00

README.txt

//===----------------------------------------------------------------------===//
// C Language Family Front-end
//===----------------------------------------------------------------------===//

Welcome to Clang.  This is a compiler front-end for the C family of languages
(C, C++, Objective-C, and Objective-C++) which is built as part of the LLVM
compiler infrastructure project.

Unlike many other compiler frontends, Clang is useful for a number of things
beyond just compiling code: we intend for Clang to be host to a number of
different source-level tools.  One example of this is the Clang Static Analyzer.

If you're interested in more (including how to build Clang) it is best to read
the relevant web sites.  Here are some pointers:

Information on Clang:             http://clang.llvm.org/
Building and using Clang:         http://clang.llvm.org/get_started.html
Clang Static Analyzer:            http://clang-analyzer.llvm.org/
Information on the LLVM project:  http://llvm.org/

If you have questions or comments about Clang, a great place to discuss them is
on the Clang development mailing list:
  http://lists.llvm.org/mailman/listinfo/cfe-dev

If you find a bug in Clang, please file it in the LLVM bug tracker:
  http://llvm.org/bugs/