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| author | sfan5 <sfan5@live.de> | 2020-04-16 10:23:48 +0200 |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2020-04-16 10:23:48 +0200 |
| commit | 5cbe8437a8f7efc9c76baf23de700e96ad96b385 (patch) | |
| tree | b10dde1f949b8528e4f634ce54069fa444dc0541 | |
| parent | e8ac5a31cf12afcfddf8e3ed31e8038930edb06f (diff) | |
| download | minetest-5cbe8437a8f7efc9c76baf23de700e96ad96b385.tar.gz minetest-5cbe8437a8f7efc9c76baf23de700e96ad96b385.tar.bz2 minetest-5cbe8437a8f7efc9c76baf23de700e96ad96b385.zip | |
Swap out -ffast-math for a safe subset of optimization flags (#9682)
It caused more trouble than its worth.
fixes #3943, fixes #5330
| -rw-r--r-- | src/CMakeLists.txt | 7 | ||||
| -rw-r--r-- | src/collision.cpp | 3 |
2 files changed, 9 insertions, 1 deletions
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt index fa261547b..d5f774d77 100644 --- a/src/CMakeLists.txt +++ b/src/CMakeLists.txt @@ -713,6 +713,11 @@ else() set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DWIN32_LEAN_AND_MEAN") endif() + # Use a safe subset of flags to speed up math calculations: + # - we don't need errno or math exceptions + # - we don't deal with Inf/NaN or signed zero + set(MATH_FLAGS "-fno-math-errno -fno-trapping-math -ffinite-math-only -fno-signed-zeros") + set(CMAKE_CXX_FLAGS_RELEASE "-DNDEBUG ${RELEASE_WARNING_FLAGS} ${WARNING_FLAGS} ${OTHER_FLAGS} -Wall -pipe -funroll-loops") if(CMAKE_SYSTEM_NAME MATCHES "(Darwin|BSD|DragonFly)") set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -Os") @@ -723,7 +728,7 @@ else() AND CMAKE_CXX_COMPILER_VERSION MATCHES "^9\\.") # Clang 9 has broken -ffast-math on glibc else() - set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -ffast-math") + set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} ${MATH_FLAGS}") endif() endif(CMAKE_SYSTEM_NAME MATCHES "(Darwin|BSD|DragonFly)") set(CMAKE_CXX_FLAGS_SEMIDEBUG "-g -O1 -Wall -Wabi ${WARNING_FLAGS} ${OTHER_FLAGS}") diff --git a/src/collision.cpp b/src/collision.cpp index 6d24bc699..a089f3377 100644 --- a/src/collision.cpp +++ b/src/collision.cpp @@ -32,6 +32,9 @@ with this program; if not, write to the Free Software Foundation, Inc., #include "util/timetaker.h" #include "profiler.h" +#ifdef __FAST_MATH__ +#warning "-ffast-math is known to cause bugs in collision code, do not use!" +#endif struct NearbyCollisionInfo { NearbyCollisionInfo(bool is_ul, bool is_obj, int bouncy, |