From c777cd5060babc0bc1ee4741b804c51ec2ea8caa Mon Sep 17 00:00:00 2001
From: orbitcowboy <orbitcowboy@web.de>
Date: Sat, 9 Jul 2022 17:32:32 +0200
Subject: [PATCH] Fixed zerodiv FN for '1/std::ceil(0)'

---
 cfg/std.cfg           |  6 +++---
 lib/programmemory.cpp | 11 +++++++++++
 test/cfg/std.cpp      |  7 +++++++
 3 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/cfg/std.cfg b/cfg/std.cfg
index f361de025..16bf335c8 100644
--- a/cfg/std.cfg
+++ b/cfg/std.cfg
@@ -965,7 +965,7 @@
   <function name="ceil,std::ceil">
     <use-retval/>
     <pure/>
-    <returnValue type="double"/>
+    <returnValue type="double">ceil(arg1)</returnValue>
     <noreturn>false</noreturn>
     <leak-ignore/>
     <arg nr="1" direction="in">
@@ -976,7 +976,7 @@
   <function name="ceilf,std::ceilf">
     <use-retval/>
     <pure/>
-    <returnValue type="float"/>
+    <returnValue type="float">ceil(arg1)</returnValue>
     <noreturn>false</noreturn>
     <leak-ignore/>
     <arg nr="1" direction="in">
@@ -987,7 +987,7 @@
   <function name="ceill,std::ceill">
     <use-retval/>
     <pure/>
-    <returnValue type="long double"/>
+    <returnValue type="long double">ceil(arg1)</returnValue>
     <noreturn>false</noreturn>
     <leak-ignore/>
     <arg nr="1" direction="in">
diff --git a/lib/programmemory.cpp b/lib/programmemory.cpp
index 4588f376a..c00c4d5cc 100644
--- a/lib/programmemory.cpp
+++ b/lib/programmemory.cpp
@@ -741,6 +741,17 @@ static std::unordered_map<std::string, BuiltinLibraryFunction> createBuiltinLibr
         v.valueType = ValueFlow::Value::ValueType::FLOAT;
         return v;
     };
+    functions["ceil"] = [](const std::vector<ValueFlow::Value>& args) {
+        if (args.size() != 1)
+            return ValueFlow::Value::unknown();
+        ValueFlow::Value v = args[0];
+        if (!v.isFloatValue() && !v.isIntValue())
+            return ValueFlow::Value::unknown();
+        double value = args[0].isFloatValue() ? args[0].floatValue : args[0].intvalue;
+        v.floatValue = std::ceil(value);
+        v.valueType = ValueFlow::Value::ValueType::FLOAT;
+        return v;
+    };
     functions["exp"] = [](const std::vector<ValueFlow::Value>& args) {
         if (args.size() != 1)
             return ValueFlow::Value::unknown();
diff --git a/test/cfg/std.cpp b/test/cfg/std.cpp
index 667879757..4f249cef8 100644
--- a/test/cfg/std.cpp
+++ b/test/cfg/std.cpp
@@ -36,6 +36,13 @@
 #include <iterator>
 #include <vector>
 
+int zerodiv_ceil()
+{
+    int i = std::ceil(0);
+    // cppcheck-suppress zerodiv
+    return 42 / i;
+}
+
 int zerodiv_sqrt()
 {
     int i = std::sqrt(0);