From 9bb091a8fc3c673dc24fed6a28da204e0ef98ac2 Mon Sep 17 00:00:00 2001
From: peter klausler <pklausler@nvidia.com>
Date: Tue, 21 Jul 2020 17:21:08 -0700
Subject: [PATCH] [flang] Handle leading zeroes after decimal in REAL formatted
 input

Leading zero digits after the decimal mark were being dropped.

Reviewed By: sscalpone

Differential Revision: https://reviews.llvm.org/D84282
---
 flang/runtime/edit-input.cpp      | 4 ++--
 flang/unittests/Runtime/hello.cpp | 5 +++++
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/flang/runtime/edit-input.cpp b/flang/runtime/edit-input.cpp
index dd708c7bfb91..9af2dbeb244c 100644
--- a/flang/runtime/edit-input.cpp
+++ b/flang/runtime/edit-input.cpp
@@ -177,8 +177,8 @@ static int ScanRealInput(char *buffer, int bufferSize, IoStatementState &io,
           continue;
         }
       }
-      if (ch == '0' && got == start) {
-        // omit leading zeroes
+      if (ch == '0' && got == start && !decimalPoint) {
+        // omit leading zeroes before the decimal
       } else if (ch >= '0' && ch <= '9') {
         if (got < bufferSize) {
           buffer[got++] = ch;
diff --git a/flang/unittests/Runtime/hello.cpp b/flang/unittests/Runtime/hello.cpp
index ff806523eb5f..71d49437bfcc 100644
--- a/flang/unittests/Runtime/hello.cpp
+++ b/flang/unittests/Runtime/hello.cpp
@@ -420,11 +420,16 @@ int main() {
   realInTest("(F18.0)", "                 0", 0x0);
   realInTest("(F18.0)", "                  ", 0x0);
   realInTest("(F18.0)", "                -0", 0x8000000000000000);
+  realInTest("(F18.0)", "                01", 0x3ff0000000000000);
   realInTest("(F18.0)", "                 1", 0x3ff0000000000000);
   realInTest("(F18.0)", "              125.", 0x405f400000000000);
   realInTest("(F18.0)", "              12.5", 0x4029000000000000);
   realInTest("(F18.0)", "              1.25", 0x3ff4000000000000);
+  realInTest("(F18.0)", "             01.25", 0x3ff4000000000000);
   realInTest("(F18.0)", "              .125", 0x3fc0000000000000);
+  realInTest("(F18.0)", "             0.125", 0x3fc0000000000000);
+  realInTest("(F18.0)", "             .0625", 0x3fb0000000000000);
+  realInTest("(F18.0)", "            0.0625", 0x3fb0000000000000);
   realInTest("(F18.0)", "               125", 0x405f400000000000);
   realInTest("(F18.1)", "               125", 0x4029000000000000);
   realInTest("(F18.2)", "               125", 0x3ff4000000000000);