[clang] bd1fac2 - Add assert on End iteration distance to Rewriter::getRewrittenText.
Yitzhak Mandelbaum via cfe-commits
cfe-commits at lists.llvm.org
Tue Jan 25 09:27:59 PST 2022
Author: Ashley Hedberg
Date: 2022-01-25T17:26:13Z
New Revision: bd1fac2fafd7a1afacce05cd53a3741a2214f5f1
URL: https://github.com/llvm/llvm-project/commit/bd1fac2fafd7a1afacce05cd53a3741a2214f5f1
DIFF: https://github.com/llvm/llvm-project/commit/bd1fac2fafd7a1afacce05cd53a3741a2214f5f1.diff
LOG: Add assert on End iteration distance to Rewriter::getRewrittenText.
I currently have code that is crashing in the second std::advance call,
and it was not straightforward to identify the problem, as the first line
of the stacktrace is in RopePieceBTreeIterator::operator++:
```
*** SIGILL; stack trace: ***
PC: clang/include/clang/Rewrite/Core/RewriteRope.h:119 clang::RopePieceBTreeIterator::operator++()
../include/c++/v1/__iterator/advance.h:35 std::__u::__advance<>()
../include/c++/v1/__iterator/advance.h:65 std::__u::advance<>()
clang/lib/Rewrite/Rewriter.cpp:228 clang::Rewriter::getRewrittenText()
clang/include/clang/Rewrite/Core/Rewriter.h:106 clang::Rewriter::getRewrittenText()
```
Adding an assertion produces a friendlier error message for the caller.
Reviewed By: gribozavr2
Differential Revision: https://reviews.llvm.org/D117579
Added:
Modified:
clang/lib/Rewrite/Rewriter.cpp
Removed:
################################################################################
diff --git a/clang/lib/Rewrite/Rewriter.cpp b/clang/lib/Rewrite/Rewriter.cpp
index 3b06afc76e16e..8950bfb7c4dcc 100644
--- a/clang/lib/Rewrite/Rewriter.cpp
+++ b/clang/lib/Rewrite/Rewriter.cpp
@@ -223,6 +223,7 @@ std::string Rewriter::getRewrittenText(CharSourceRange Range) const {
RewriteBuffer::iterator Start = RB.begin();
std::advance(Start, StartOff);
RewriteBuffer::iterator End = Start;
+ assert(EndOff >= StartOff && "Invalid iteration distance");
std::advance(End, EndOff-StartOff);
return std::string(Start, End);
More information about the cfe-commits
mailing list