Message ID | 20220111082900.3341274-1-peter.maydell@linaro.org |
---|---|
State | Accepted |
Commit | b37778b840f6dc6d1bbaf0e8e0641b3d48ad77c5 |
Headers | show |
Series | [v2] linux-user: Fix clang warning for nios2-linux-user code | expand |
Le 11/01/2022 à 09:29, Peter Maydell a écrit : > The clang in Ubuntu 18.04 (10.0.0-4ubuntu1) produces a warning > on the code added in commit f5ef0e518d03 where we use a > shifted expression in a boolean context: > > ../../linux-user/elfload.c:2423:16: error: converting the result of '<<' to a boolean always evaluates to true [-Werror,-Wtautological-constant-compare] > } else if (LO_COMMPAGE) { > ^ > ../../linux-user/elfload.c:1102:22: note: expanded from macro 'LO_COMMPAGE' > #define LO_COMMPAGE TARGET_PAGE_SIZE > ^ > /mnt/nvmedisk/linaro/qemu-from-laptop/qemu/include/exec/cpu-all.h:231:31: note: expanded from macro 'TARGET_PAGE_SIZE' > #define TARGET_PAGE_SIZE (1 << TARGET_PAGE_BITS) > ^ > 1 error generated. > > The warning is bogus because whether LO_COMMPAGE is zero or not > depends on compile-time ifdefs; shut the compiler up by adding > an explicit comparison to zero. > > Fixes: f5ef0e518d0331 ("linux-user/nios2: Map a real kuser page") > Signed-off-by: Peter Maydell <peter.maydell@linaro.org> > --- > v1->v2: fix sense of comparison (oops!) > > linux-user/elfload.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/linux-user/elfload.c b/linux-user/elfload.c > index 329b2375ef1..d3274edfdb7 100644 > --- a/linux-user/elfload.c > +++ b/linux-user/elfload.c > @@ -2420,7 +2420,7 @@ static void pgb_static(const char *image_name, abi_ulong orig_loaddr, > } else { > offset = -(HI_COMMPAGE & -align); > } > - } else if (LO_COMMPAGE) { > + } else if (LO_COMMPAGE != 0) { > loaddr = MIN(loaddr, LO_COMMPAGE & -align); > } > Reviewed-by: Laurent Vivier <laurent@vivier.eu>
On Tue, 11 Jan 2022 at 09:00, Laurent Vivier <laurent@vivier.eu> wrote: > > Le 11/01/2022 à 09:29, Peter Maydell a écrit : > > The clang in Ubuntu 18.04 (10.0.0-4ubuntu1) produces a warning > > on the code added in commit f5ef0e518d03 where we use a > > shifted expression in a boolean context: > > > > ../../linux-user/elfload.c:2423:16: error: converting the result of '<<' to a boolean always evaluates to true [-Werror,-Wtautological-constant-compare] > > } else if (LO_COMMPAGE) { > > ^ > > ../../linux-user/elfload.c:1102:22: note: expanded from macro 'LO_COMMPAGE' > > #define LO_COMMPAGE TARGET_PAGE_SIZE > > ^ > > /mnt/nvmedisk/linaro/qemu-from-laptop/qemu/include/exec/cpu-all.h:231:31: note: expanded from macro 'TARGET_PAGE_SIZE' > > #define TARGET_PAGE_SIZE (1 << TARGET_PAGE_BITS) > > ^ > > 1 error generated. > > > > The warning is bogus because whether LO_COMMPAGE is zero or not > > depends on compile-time ifdefs; shut the compiler up by adding > > an explicit comparison to zero. > > > > Fixes: f5ef0e518d0331 ("linux-user/nios2: Map a real kuser page") > > Signed-off-by: Peter Maydell <peter.maydell@linaro.org> > > --- > > v1->v2: fix sense of comparison (oops!) > > > > linux-user/elfload.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/linux-user/elfload.c b/linux-user/elfload.c > > index 329b2375ef1..d3274edfdb7 100644 > > --- a/linux-user/elfload.c > > +++ b/linux-user/elfload.c > > @@ -2420,7 +2420,7 @@ static void pgb_static(const char *image_name, abi_ulong orig_loaddr, > > } else { > > offset = -(HI_COMMPAGE & -align); > > } > > - } else if (LO_COMMPAGE) { > > + } else if (LO_COMMPAGE != 0) { > > loaddr = MIN(loaddr, LO_COMMPAGE & -align); > > } > > > > Reviewed-by: Laurent Vivier <laurent@vivier.eu> Thanks; applied to master as a build fix. -- PMM
diff --git a/linux-user/elfload.c b/linux-user/elfload.c index 329b2375ef1..d3274edfdb7 100644 --- a/linux-user/elfload.c +++ b/linux-user/elfload.c @@ -2420,7 +2420,7 @@ static void pgb_static(const char *image_name, abi_ulong orig_loaddr, } else { offset = -(HI_COMMPAGE & -align); } - } else if (LO_COMMPAGE) { + } else if (LO_COMMPAGE != 0) { loaddr = MIN(loaddr, LO_COMMPAGE & -align); }
The clang in Ubuntu 18.04 (10.0.0-4ubuntu1) produces a warning on the code added in commit f5ef0e518d03 where we use a shifted expression in a boolean context: ../../linux-user/elfload.c:2423:16: error: converting the result of '<<' to a boolean always evaluates to true [-Werror,-Wtautological-constant-compare] } else if (LO_COMMPAGE) { ^ ../../linux-user/elfload.c:1102:22: note: expanded from macro 'LO_COMMPAGE' #define LO_COMMPAGE TARGET_PAGE_SIZE ^ /mnt/nvmedisk/linaro/qemu-from-laptop/qemu/include/exec/cpu-all.h:231:31: note: expanded from macro 'TARGET_PAGE_SIZE' #define TARGET_PAGE_SIZE (1 << TARGET_PAGE_BITS) ^ 1 error generated. The warning is bogus because whether LO_COMMPAGE is zero or not depends on compile-time ifdefs; shut the compiler up by adding an explicit comparison to zero. Fixes: f5ef0e518d0331 ("linux-user/nios2: Map a real kuser page") Signed-off-by: Peter Maydell <peter.maydell@linaro.org> --- v1->v2: fix sense of comparison (oops!) linux-user/elfload.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)