diff --git a/modules/etc/SCsub b/modules/etc/SCsub
index d2c77d6e3c08..6e963ef766d8 100644
--- a/modules/etc/SCsub
+++ b/modules/etc/SCsub
@@ -33,11 +33,6 @@ env_etc.Append(CPPPATH=[thirdparty_dir])
 if not env.msvc:
 	env_etc.Append(CCFLAGS="-std=c++11")
 
-# -ffast-math seems to be incompatible with etc2comp on recent versions of
-# GCC and Clang
-if '-ffast-math' in env_etc['CCFLAGS']:
-	env_etc['CCFLAGS'].remove('-ffast-math')
-
 env_thirdparty = env_etc.Clone()
 env_thirdparty.disable_warnings()
 env_thirdparty.add_source_files(env.modules_sources, thirdparty_sources)
diff --git a/platform/android/detect.py b/platform/android/detect.py
index 7a728e4ef169..b031e51d8c4f 100644
--- a/platform/android/detect.py
+++ b/platform/android/detect.py
@@ -141,7 +141,7 @@ def mySpawn(sh, escape, cmd, args, env):
     if (env["target"].startswith("release")):
         if (env["optimize"] == "speed"): #optimize for speed (default)
             env.Append(LINKFLAGS=['-O2'])
-            env.Append(CPPFLAGS=['-O2', '-DNDEBUG', '-ffast-math', '-funsafe-math-optimizations', '-fomit-frame-pointer'])
+            env.Append(CPPFLAGS=['-O2', '-DNDEBUG', '-fomit-frame-pointer'])
         else: #optimize for size
             env.Append(CPPFLAGS=['-Os', '-DNDEBUG'])
             env.Append(LINKFLAGS=['-Os'])
diff --git a/platform/haiku/detect.py b/platform/haiku/detect.py
index 8d704ac65700..ae8cc58a4a05 100644
--- a/platform/haiku/detect.py
+++ b/platform/haiku/detect.py
@@ -37,14 +37,14 @@ def configure(env):
     ## Build type
 
     if (env["target"] == "release"):
-        env.Prepend(CCFLAGS=['-O3', '-ffast-math'])
+        env.Prepend(CCFLAGS=['-O3'])
         if (env["debug_symbols"] == "yes"):
             env.Prepend(CCFLAGS=['-g1'])
         if (env["debug_symbols"] == "full"):
             env.Prepend(CCFLAGS=['-g2'])
 
     elif (env["target"] == "release_debug"):
-        env.Prepend(CCFLAGS=['-O2', '-ffast-math', '-DDEBUG_ENABLED'])
+        env.Prepend(CCFLAGS=['-O2', '-DDEBUG_ENABLED'])
         if (env["debug_symbols"] == "yes"):
             env.Prepend(CCFLAGS=['-g1'])
         if (env["debug_symbols"] == "full"):
diff --git a/platform/iphone/detect.py b/platform/iphone/detect.py
index 20fb4428dd07..797a7d31aa3c 100644
--- a/platform/iphone/detect.py
+++ b/platform/iphone/detect.py
@@ -46,7 +46,7 @@ def configure(env):
     if (env["target"].startswith("release")):
         env.Append(CPPFLAGS=['-DNDEBUG', '-DNS_BLOCK_ASSERTIONS=1'])
         if (env["optimize"] == "speed"): #optimize for speed (default)
-            env.Append(CPPFLAGS=['-O2', '-ftree-vectorize', '-fomit-frame-pointer', '-ffast-math', '-funsafe-math-optimizations'])
+            env.Append(CPPFLAGS=['-O2', '-ftree-vectorize', '-fomit-frame-pointer'])
             env.Append(LINKFLAGS=['-O2'])
         else: #optimize for size
             env.Append(CPPFLAGS=['-Os', '-ftree-vectorize'])
diff --git a/platform/osx/detect.py b/platform/osx/detect.py
index 6eee8f204f9e..31fcbc04276d 100644
--- a/platform/osx/detect.py
+++ b/platform/osx/detect.py
@@ -42,7 +42,7 @@ def configure(env):
 
     if (env["target"] == "release"):
         if (env["optimize"] == "speed"): #optimize for speed (default)
-            env.Prepend(CCFLAGS=['-O3', '-ffast-math', '-fomit-frame-pointer', '-ftree-vectorize', '-msse2'])
+            env.Prepend(CCFLAGS=['-O3', '-fomit-frame-pointer', '-ftree-vectorize', '-msse2'])
         else: #optimize for size
             env.Prepend(CCFLAGS=['-Os','-ftree-vectorize', '-msse2'])
 
diff --git a/platform/server/detect.py b/platform/server/detect.py
index 0b23e9c64912..392a987ee98f 100644
--- a/platform/server/detect.py
+++ b/platform/server/detect.py
@@ -43,10 +43,10 @@ def configure(env):
     ## Build type
 
     if (env["target"] == "release"):
-        env.Append(CCFLAGS=['-O2', '-ffast-math', '-fomit-frame-pointer'])
+        env.Append(CCFLAGS=['-O2', '-fomit-frame-pointer'])
 
     elif (env["target"] == "release_debug"):
-        env.Append(CCFLAGS=['-O2', '-ffast-math', '-DDEBUG_ENABLED'])
+        env.Append(CCFLAGS=['-O2', '-DDEBUG_ENABLED'])
 
     elif (env["target"] == "debug"):
         env.Append(CCFLAGS=['-g2', '-DDEBUG_ENABLED', '-DDEBUG_MEMORY_ENABLED'])
diff --git a/platform/x11/detect.py b/platform/x11/detect.py
index 9b6fb2f4784f..415e8ceaa6ed 100644
--- a/platform/x11/detect.py
+++ b/platform/x11/detect.py
@@ -86,10 +86,8 @@ def configure(env):
     ## Build type
 
     if (env["target"] == "release"):
-        # -O3 -ffast-math is identical to -Ofast. We need to split it out so we can selectively disable
-        # -ffast-math in code for which it generates wrong results.
         if (env["optimize"] == "speed"): #optimize for speed (default)
-            env.Prepend(CCFLAGS=['-O3', '-ffast-math'])
+            env.Prepend(CCFLAGS=['-O3'])
         else: #optimize for size
             env.Prepend(CCFLAGS=['-Os'])
 
@@ -100,7 +98,7 @@ def configure(env):
 
     elif (env["target"] == "release_debug"):
         if (env["optimize"] == "speed"): #optimize for speed (default)
-            env.Prepend(CCFLAGS=['-O2', '-ffast-math', '-DDEBUG_ENABLED'])
+            env.Prepend(CCFLAGS=['-O2', '-DDEBUG_ENABLED'])
         else: #optimize for size
             env.Prepend(CCFLAGS=['-Os', '-DDEBUG_ENABLED'])