[JSON] Work around excess-precision issue when comparing T_Integer numbers.
Reviewers: bkramer
Subscribers: kristina, llvm-commits
Differential Revision: https://reviews.llvm.org/D57237
llvm-svn: 352204
diff --git a/llvm/lib/Support/JSON.cpp b/llvm/lib/Support/JSON.cpp
index 4b67536..790b28f 100644
--- a/llvm/lib/Support/JSON.cpp
+++ b/llvm/lib/Support/JSON.cpp
@@ -181,6 +181,12 @@
case Value::Boolean:
return *L.getAsBoolean() == *R.getAsBoolean();
case Value::Number:
+ // Workaround for https://gcc.gnu.org/bugzilla/show_bug.cgi?id=323
+ // The same integer must convert to the same double, per the standard.
+ // However we see 64-vs-80-bit precision comparisons with gcc-7 -O3 -m32.
+ // So we avoid floating point promotion for exact comparisons.
+ if (L.Type == Value::T_Integer || R.Type == Value::T_Integer)
+ return L.getAsInteger() == R.getAsInteger();
return *L.getAsNumber() == *R.getAsNumber();
case Value::String:
return *L.getAsString() == *R.getAsString();