Speed up compilation by avoiding generating exceptional edges from

CallExprs as those edges help cause a n^2 explosion in the number of
destructor calls.  Other consumers, such as static analysis, that
would like to have more a more complete CFG can select the inclusion
of those edges as CFG build time.

This also fixes up the two compilation users of CFGs to be tolerant of
having or not having those edges.  All catch code is assumed be to
live if we didn't generate the exceptional edges for CallExprs.

llvm-svn: 94074

1 files changed, 35 insertions, 0 deletions

diff --git a/clang/test/SemaCXX/warn-unreachable.cpp b/clang/test/SemaCXX/warn-unreachable.cpp
new file mode 100644
index 00000000000..13a82f4f183
--- /dev/null
+++ b/clang/test/SemaCXX/warn-unreachable.cpp
@@ -0,0 +1,35 @@
+// RUN: %clang %s -fsyntax-only -Xclang -verify -fblocks -Wunreachable-code -Wno-unused-value
+
+int live();
+int dead();
+int liveti() throw(int);
+int (*livetip)() throw(int);
+
+int test1() {
+  try {
+    live();
+  } catch (int i) {
+    live();
+  }
+  return 1;
+}
+
+void test2() {
+  try {
+    live();
+  } catch (int i) {
+    live();
+  }
+  try {
+    liveti();
+  } catch (int i) {
+    live();
+  }
+  try {
+    livetip();
+  } catch (int i) {
+    live();
+  }
+  throw 1;
+  dead();       // expected-warning {{will never be executed}}
+}