[clang] Fix segmentation fault caused by stack overflow on deeply nested expressions (#111701)

Done by calling clang::runWithSufficientStackSpace().
Added CodeGenModule::runWithSufficientStackSpace() method similar to the
one in Sema to provide a single warning when this triggers
Fixes: #111699

1 files changed, 11 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CodeGenModule.h b/clang/lib/CodeGen/CodeGenModule.h
index c58bb88..57e06cb 100644
--- a/clang/lib/CodeGen/CodeGenModule.h
+++ b/clang/lib/CodeGen/CodeGenModule.h
@@ -336,6 +336,7 @@ private:
   std::unique_ptr<llvm::IndexedInstrProfReader> PGOReader;
   InstrProfStats PGOStats;
   std::unique_ptr<llvm::SanitizerStatReport> SanStats;
+  bool WarnedStackExhausted = false;
 
   // A set of references that have only been seen via a weakref so far. This is
   // used to remove the weak of the reference if we ever see a direct reference
@@ -1297,6 +1298,16 @@ public:
   /// Print out an error that codegen doesn't support the specified decl yet.
   void ErrorUnsupported(const Decl *D, const char *Type);
 
+  /// Warn that the stack is nearly exhausted.
+  void warnStackExhausted(SourceLocation Loc);
+
+  /// Run some code with "sufficient" stack space. (Currently, at least 256K is
+  /// guaranteed). Produces a warning if we're low on stack space and allocates
+  /// more in that case. Use this in code that may recurse deeply to avoid stack
+  /// overflow.
+  void runWithSufficientStackSpace(SourceLocation Loc,
+                                   llvm::function_ref<void()> Fn);
+
   /// Set the attributes on the LLVM function for the given decl and function
   /// info. This applies attributes necessary for handling the ABI as well as
   /// user specified attributes like section.