[Support/GlobPattern] - Do not crash when pattern has characters with int value < 0.

Found it during work on LLD, it would crash on following 
linker script:

SECTIONS { .foo : { *("*®") } }
That happens because ® has int value -82. And chars are used as
array index in code, and are signed by default.

Differential revision: https://reviews.llvm.org/D35891

llvm-svn: 309549

1 files changed, 9 insertions, 0 deletions

diff --git a/llvm/unittests/Support/GlobPatternTest.cpp b/llvm/unittests/Support/GlobPatternTest.cpp
index 44d77266db1..d7016ab218d 100644
--- a/llvm/unittests/Support/GlobPatternTest.cpp
+++ b/llvm/unittests/Support/GlobPatternTest.cpp
@@ -67,4 +67,13 @@ TEST_F(GlobPatternTest, Invalid) {
   EXPECT_FALSE((bool)Pat1);
   handleAllErrors(Pat1.takeError(), [&](ErrorInfoBase &EIB) {});
 }
+
+TEST_F(GlobPatternTest, ExtSym) {
+  Expected<GlobPattern> Pat1 = GlobPattern::create("a*\xFF");
+  EXPECT_TRUE((bool)Pat1);
+  EXPECT_TRUE(Pat1->match("axxx\xFF"));
+  Expected<GlobPattern> Pat2 = GlobPattern::create("[\xFF-\xFF]");
+  EXPECT_TRUE((bool)Pat2);
+  EXPECT_TRUE(Pat2->match("\xFF"));
+}
 }