2019-04-18 12:16 GMT+02:00, Michael Niedermayer <mich...@niedermayer.cc>: > On Tue, Apr 16, 2019 at 12:55:03AM +0200, Carl Eugen Hoyos wrote: >> 2019-04-14 1:02 GMT+02:00, Michael Niedermayer <mich...@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 <ceffm...@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 <ceffm...@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 ?
Attached patch also avoids the warning. Thank you, Carl Eugen
From 69c7f0894acccf64438198cd8d01a9f3e9765a95 Mon Sep 17 00:00:00 2001 From: Carl Eugen Hoyos <ceffm...@gmail.com> Date: Thu, 18 Apr 2019 14:05:21 +0200 Subject: [PATCH] lavfi/fspp: Simplify a macro. 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..73d8c7c 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) ((x) * (1 << s) + 0.5) #define MULTIPLY16H(x,k) (((x) * (k)) >> 16) #define THRESHOLD(r,x,t) \ -- 1.7.10.4
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