From: David Bolvansky <david.bolvansky@gmail.com>
Date: Mon, 23 Sep 2019 09:58:02 +0000 (+0000)
Subject: [FunctionAttrs] Enable nonnull arg propagation
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=13cfd6ccddc727b5f7f39c431d101df316499f4f;p=llvm

[FunctionAttrs] Enable nonnull arg propagation

Enable flag introduced in rL294998. Security concerns are no longer valid, since function signatures for mentioned libc functions has no nonnull attribute (Clang does not generate them? I see no nonnull attr in LLVM IR for these functions) and since rL372091 we carefully annotate the callsites where we know that size is static, non zero. So let's enable this flag again..




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@372573 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Transforms/IPO/FunctionAttrs.cpp b/lib/Transforms/IPO/FunctionAttrs.cpp
index 0e923a717e6..b174c63a577 100644
--- a/lib/Transforms/IPO/FunctionAttrs.cpp
+++ b/lib/Transforms/IPO/FunctionAttrs.cpp
@@ -78,11 +78,8 @@ STATISTIC(NumNoRecurse, "Number of functions marked as norecurse");
 STATISTIC(NumNoUnwind, "Number of functions marked as nounwind");
 STATISTIC(NumNoFree, "Number of functions marked as nofree");
 
-// FIXME: This is disabled by default to avoid exposing security vulnerabilities
-// in C/C++ code compiled by clang:
-// http://lists.llvm.org/pipermail/cfe-dev/2017-January/052066.html
 static cl::opt<bool> EnableNonnullArgPropagation(
-    "enable-nonnull-arg-prop", cl::Hidden,
+    "enable-nonnull-arg-prop", cl::init(true), cl::Hidden,
     cl::desc("Try to propagate nonnull argument attributes from callsites to "
              "caller functions."));