| Message ID | CAB0OVGqHb8tt375wDRAG7md0wis-t3m83q_uQ_vjEKOCNQ3_hw@mail.gmail.com |
|---|---|
| State | Superseded |
| Headers | show |
On Tue, Apr 16, 2019 at 12:55:03AM +0200, Carl Eugen Hoyos wrote: > 2019-04-14 1:02 GMT+02:00, Michael Niedermayer <michael@niedermayer.cc>: > > On Sat, Apr 13, 2019 at 07:25:54PM -0300, James Almer wrote: > >> On 4/13/2019 7:04 PM, Carl Eugen Hoyos wrote: > >> > Hi! > >> > > >> > Attached patch silences two warnings shown when compiling with clang: > >> > libavfilter/vf_fspp.h:51:42: warning: implicit conversion from 'int' > >> > to 'int16_t' (aka 'short') changes value from 44130 to -21406 > >> > > >> > Please comment, Carl Eugen > >> > > >> > > >> > 0001-lavfi-vf_fspp-Use-the-intended-cast-to-int16_t.patch > >> > > >> > From d731e523d9c5854183d20d37fe921f49fb048498 Mon Sep 17 00:00:00 2001 > >> > From: Carl Eugen Hoyos <ceffmpeg@gmail.com> > >> > Date: Sat, 13 Apr 2019 23:05:44 +0200 > >> > Subject: [PATCH] lavfi/fspp: Add two casts to int16_t. > >> > > >> > Silences a warning with clang: > >> > warning: implicit conversion from 'int' to 'int16_t' (aka 'short') > >> > changes value from 44130 to -21406 > >> > --- > >> > libavfilter/vf_fspp.h | 2 +- > >> > 1 file changed, 1 insertion(+), 1 deletion(-) > >> > > >> > diff --git a/libavfilter/vf_fspp.h b/libavfilter/vf_fspp.h > >> > index 74a3447..e346439 100644 > >> > --- a/libavfilter/vf_fspp.h > >> > +++ b/libavfilter/vf_fspp.h > >> > @@ -31,7 +31,7 @@ > >> > #define DCTSIZE 8 > >> > #define DCTSIZE_S "8" > >> > > >> > -#define FIX(x,s) ((int) ((x) * (1 << s) + 0.5) & 0xffff) > >> > +#define FIX(x,s) ((int16_t)((x) * (1 << s) + 0.5) & (int16_t)0xffff) > >> > >> The "& 0xffff" is turning -21406 into 44130 since it zeroes all the high > >> bits, and then that value gets converted back to -21406 when stored into > >> an int16_t variable. > >> > >> Change the int cast into int16_t if you want since it doesn't hurt (all > >> the values are safely within the int16_t range anyway), but remove the > >> "& 0xffff" altogether instead of casting it, to get rid of this warning. > >> > >> > #define C64(x) ((uint64_t)((x) | (x) << 16)) <<32 | (uint64_t)(x) | > >> > (uint64_t)(x) << 16 > >> > #define FIX64(x,s) C64(FIX(x,s)) > > > > i think the C64 / FIX64 macros depend on the & 0xFFFF. They are maybe > > unused > > and just referenced in comments but having them not give correct values > > could still be confusing. The 0xFFFF if its removed should be added to the > > code / comments that refer to it in a way that needs it > > New patch attached. > Not sure if / where to add comments. > > Please comment, Carl Eugen > vf_fspp.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > 17e468ee43988ef39d3ce882774dc3e2d625c9e6 0001-lavfi-fspp-Cast-float-values-to-int16_t-instead-of-i.patch > From dfda9d8a6714649015f252e0e0bf5e3e52ce1b5c Mon Sep 17 00:00:00 2001 > From: Carl Eugen Hoyos <ceffmpeg@gmail.com> > Date: Tue, 16 Apr 2019 00:50:50 +0200 > Subject: [PATCH] lavfi/fspp: Cast float values to int16_t instead of int. > > Silences a warning with clang: > warning: implicit conversion from 'int' to 'int16_t' (aka 'short') changes value from 44130 to -21406 > --- > libavfilter/vf_fspp.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/libavfilter/vf_fspp.h b/libavfilter/vf_fspp.h > index 802db14..bdafe8e 100644 > --- a/libavfilter/vf_fspp.h > +++ b/libavfilter/vf_fspp.h > @@ -31,7 +31,7 @@ > #define DCTSIZE 8 > #define DCTSIZE_S "8" > > -#define FIX(x,s) ((int) ((x) * (1 << s) + 0.5) & 0xffff) > +#define FIX(x,s) ((int16_t)((x) * (1 << s) + 0.5)) does it need the cast at all to avoid the warning ? [...]
From dfda9d8a6714649015f252e0e0bf5e3e52ce1b5c Mon Sep 17 00:00:00 2001 From: Carl Eugen Hoyos <ceffmpeg@gmail.com> Date: Tue, 16 Apr 2019 00:50:50 +0200 Subject: [PATCH] lavfi/fspp: Cast float values to int16_t instead of int. Silences a warning with clang: warning: implicit conversion from 'int' to 'int16_t' (aka 'short') changes value from 44130 to -21406 --- libavfilter/vf_fspp.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libavfilter/vf_fspp.h b/libavfilter/vf_fspp.h index 802db14..bdafe8e 100644 --- a/libavfilter/vf_fspp.h +++ b/libavfilter/vf_fspp.h @@ -31,7 +31,7 @@ #define DCTSIZE 8 #define DCTSIZE_S "8" -#define FIX(x,s) ((int) ((x) * (1 << s) + 0.5) & 0xffff) +#define FIX(x,s) ((int16_t)((x) * (1 << s) + 0.5)) #define MULTIPLY16H(x,k) (((x) * (k)) >> 16) #define THRESHOLD(r,x,t) \ -- 1.7.10.4