diff --git a/Userland/Libraries/LibM/math.cpp b/Userland/Libraries/LibM/math.cpp
index e0cd0a8a1a..068dfb7d88 100644
--- a/Userland/Libraries/LibM/math.cpp
+++ b/Userland/Libraries/LibM/math.cpp
@@ -28,6 +28,7 @@
 #include <AK/Platform.h>
 #include <AK/StdLibExtras.h>
 #include <LibC/assert.h>
+#include <fenv.h>
 #include <math.h>
 #include <stdint.h>
 #include <stdlib.h>
@@ -61,10 +62,10 @@ template<size_t value>
 constexpr size_t product_odd() { return value * product_odd<value - 2>(); }
 
 enum class RoundingMode {
-    ToZero,
-    Up,
-    Down,
-    ToEven
+    ToZero = FE_TOWARDZERO,
+    Up = FE_UPWARD,
+    Down = FE_DOWNWARD,
+    ToEven = FE_TONEAREST
 };
 
 template<typename T>
@@ -307,6 +308,16 @@ double trunc(double x) NOEXCEPT
     return internal_to_integer(x, RoundingMode::ToZero);
 }
 
+float truncf(float x) NOEXCEPT
+{
+    return internal_to_integer(x, RoundingMode::ToZero);
+}
+
+long double truncl(long double x) NOEXCEPT
+{
+    return internal_to_integer(x, RoundingMode::ToZero);
+}
+
 double cos(double angle) NOEXCEPT
 {
     return sin(angle + M_PI_2);
@@ -691,6 +702,11 @@ float roundf(float value) NOEXCEPT
     return internal_to_integer(value, RoundingMode::ToEven);
 }
 
+long double roundl(long double value) NOEXCEPT
+{
+    return internal_to_integer(value, RoundingMode::ToEven);
+}
+
 float floorf(float value) NOEXCEPT
 {
     return internal_to_integer(value, RoundingMode::Down);
@@ -701,10 +717,54 @@ double floor(double value) NOEXCEPT
     return internal_to_integer(value, RoundingMode::Down);
 }
 
+long double floorl(long double value) NOEXCEPT
+{
+    return internal_to_integer(value, RoundingMode::Down);
+}
+
+long double rintl(long double value) NOEXCEPT
+{
+    return internal_to_integer(value, RoundingMode { fegetround() });
+}
+
 double rint(double value) NOEXCEPT
 {
-    // This should be the current rounding mode
-    return internal_to_integer(value, RoundingMode::ToEven);
+    return internal_to_integer(value, RoundingMode { fegetround() });
+}
+
+float rintf(float value) NOEXCEPT
+{
+    return internal_to_integer(value, RoundingMode { fegetround() });
+}
+
+long lrintl(long double value) NOEXCEPT
+{
+    return (long)internal_to_integer(value, RoundingMode { fegetround() });
+}
+
+long lrint(double value) NOEXCEPT
+{
+    return (long)internal_to_integer(value, RoundingMode { fegetround() });
+}
+
+long lrintf(float value) NOEXCEPT
+{
+    return (long)internal_to_integer(value, RoundingMode { fegetround() });
+}
+
+long long llrintl(long double value) NOEXCEPT
+{
+    return (long long)internal_to_integer(value, RoundingMode { fegetround() });
+}
+
+long long llrint(double value) NOEXCEPT
+{
+    return (long long)internal_to_integer(value, RoundingMode { fegetround() });
+}
+
+long long llrintf(float value) NOEXCEPT
+{
+    return (long long)internal_to_integer(value, RoundingMode { fegetround() });
 }
 
 float ceilf(float value) NOEXCEPT
@@ -717,6 +777,11 @@ double ceil(double value) NOEXCEPT
     return internal_to_integer(value, RoundingMode::Up);
 }
 
+long double ceill(long double value) NOEXCEPT
+{
+    return internal_to_integer(value, RoundingMode::Up);
+}
+
 double modf(double x, double* intpart) NOEXCEPT
 {
     double integer_part = internal_to_integer(x, RoundingMode::ToZero);
diff --git a/Userland/Libraries/LibM/math.h b/Userland/Libraries/LibM/math.h
index db6b7373d9..5f769fbc2d 100644
--- a/Userland/Libraries/LibM/math.h
+++ b/Userland/Libraries/LibM/math.h
@@ -99,12 +99,24 @@ double tanh(double) NOEXCEPT;
 float tanhf(float) NOEXCEPT;
 double ceil(double) NOEXCEPT;
 float ceilf(float) NOEXCEPT;
+long double ceill(long double) NOEXCEPT;
 double floor(double) NOEXCEPT;
 float floorf(float) NOEXCEPT;
+long double floorl(long double) NOEXCEPT;
 double trunc(double) NOEXCEPT;
 float truncf(float) NOEXCEPT;
+long double truncl(long double) NOEXCEPT;
 double round(double) NOEXCEPT;
 float roundf(float) NOEXCEPT;
+long double roundl(long double) NOEXCEPT;
+double rint(double) NOEXCEPT;
+float rintf(float) NOEXCEPT;
+long lrintl(long double) NOEXCEPT;
+long lrint(double) NOEXCEPT;
+long lrintf(float) NOEXCEPT;
+long long llrintl(long double) NOEXCEPT;
+long long llrint(double) NOEXCEPT;
+long long llrintf(float) NOEXCEPT;
 double fabs(double) NOEXCEPT;
 float fabsf(float) NOEXCEPT;
 double fmod(double, double) NOEXCEPT;