From 48b80c78b02efd7c4a7e3a7530d05b8aa9d3b649 Mon Sep 17 00:00:00 2001
From: Reid Kleckner <reid@kleckner.net>
Date: Wed, 25 Sep 2013 16:42:48 +0000
Subject: [PATCH] PR17359: Fix off-by-one OOB on _Pragma("") and an unescaping
bug
Previously the code would reduce a run of backslashes to a single
backslash, and now it will properly leave behind every other backslash.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@191382 91177308-0d34-0410-b5e6-96231b3b80d8
---
lib/Lex/Pragma.cpp | 14 +++++++-------
test/Preprocessor/_Pragma.c | 3 +++
2 files changed, 10 insertions(+), 7 deletions(-)
diff --git a/lib/Lex/Pragma.cpp b/lib/Lex/Pragma.cpp
index 8d3dedc375..4c6d889bf3 100644
--- a/lib/Lex/Pragma.cpp
+++ b/lib/Lex/Pragma.cpp
@@ -263,14 +263,14 @@ void Preprocessor::Handle_Pragma(Token &Tok) {
// Remove escaped quotes and escapes.
unsigned ResultPos = 1;
- for (unsigned i = 1, e = StrVal.size() - 2; i != e; ++i) {
- if (StrVal[i] != '\\' ||
- (StrVal[i + 1] != '\\' && StrVal[i + 1] != '"')) {
- // \\ -> '\' and \" -> '"'.
- StrVal[ResultPos++] = StrVal[i];
- }
+ for (unsigned i = 1, e = StrVal.size() - 1; i != e; ++i) {
+ // Skip escapes. \\ -> '\' and \" -> '"'.
+ if (StrVal[i] == '\\' && i + 1 < e &&
+ (StrVal[i + 1] == '\\' || StrVal[i + 1] == '"'))
+ ++i;
+ StrVal[ResultPos++] = StrVal[i];
}
- StrVal.erase(StrVal.begin() + ResultPos, StrVal.end() - 2);
+ StrVal.erase(StrVal.begin() + ResultPos, StrVal.end() - 1);
}
// Remove the front quote, replacing it with a space, so that the pragma
diff --git a/test/Preprocessor/_Pragma.c b/test/Preprocessor/_Pragma.c
index 0a83b149ff..15725a4222 100644
--- a/test/Preprocessor/_Pragma.c
+++ b/test/Preprocessor/_Pragma.c
@@ -5,6 +5,9 @@ _Pragma ("GCC system_header") // expected-warning {{system_header ignored in ma
// rdar://6880630
_Pragma("#define macro") // expected-warning {{unknown pragma ignored}}
+_Pragma("") // expected-warning {{unknown pragma ignored}}
+_Pragma("message(\"foo \\\\\\\\ bar\")") // expected-warning {{foo \\ bar}}
+
#ifdef macro
#error #define invalid
#endif
--
2.40.0