From 30d7915ce44629edc85dba210cca9007d1c70d02 Mon Sep 17 00:00:00 2001 From: Mark Eggleston Date: Tue, 16 Apr 2019 09:09:12 +0100 Subject: [PATCH] Suppress warning with -Wno-overwrite-recursive The message "Warning: Flag '-fno-automatic' overwrites '-frecursive'" is output by default when -fno-automatic and -frecursive are used together. It warns that recursion may be broken, however if all the relavent variables in the recursive procedure have automatic attributes the warning is unnecessary so -Wno-overwrite-recursive can be used to suppress it. This will allow compilation when warnings are regarded as errors. Suppress warning with -Wno-overwrite-recursive --- gcc/fortran/invoke.texi | 20 +++++++++++++++----- gcc/fortran/lang.opt | 4 ++++ gcc/fortran/options.c | 3 ++- .../gfortran.dg/no_overwrite_recursive_1.f90 | 11 +++++++++++ .../gfortran.dg/no_overwrite_recursive_2.f90 | 10 ++++++++++ 5 files changed, 42 insertions(+), 6 deletions(-) create mode 100644 gcc/testsuite/gfortran.dg/no_overwrite_recursive_1.f90 create mode 100644 gcc/testsuite/gfortran.dg/no_overwrite_recursive_2.f90 diff --git a/gcc/fortran/invoke.texi b/gcc/fortran/invoke.texi index b911ac90018..0177fb400a1 100644 --- a/gcc/fortran/invoke.texi +++ b/gcc/fortran/invoke.texi @@ -149,10 +149,11 @@ and warnings}. -Wc-binding-type -Wcharacter-truncation -Wconversion @gol -Wdo-subscript -Wfunction-elimination -Wimplicit-interface @gol -Wimplicit-procedure -Wintrinsic-shadow -Wuse-without-only @gol --Wintrinsics-std -Wline-truncation -Wno-align-commons -Wno-tabs @gol --Wreal-q-constant -Wsurprising -Wunderflow -Wunused-parameter @gol --Wrealloc-lhs -Wrealloc-lhs-all -Wfrontend-loop-interchange @gol --Wtarget-lifetime -fmax-errors=@var{n} -fsyntax-only -pedantic @gol +-Wintrinsics-std -Wline-truncation -Wno-align-commons @gol +-Wno-overwrite-recursive -Wno-tabs -Wreal-q-constant -Wsurprising @gol +-Wunderflow -Wunused-parameter -Wrealloc-lhs -Wrealloc-lhs-all @gol +-Wfrontend-loop-interchange -Wtarget-lifetime -fmax-errors=@var{n} @gol +-fsyntax-only -pedantic @gol -pedantic-errors @gol } @@ -995,7 +996,7 @@ nor has been declared as @code{EXTERNAL}. @opindex @code{Winteger-division} @cindex warnings, integer division @cindex warnings, division of integers -Warn if a constant integer division truncates it result. +Warn if a constant integer division truncates its result. As an example, 3/5 evaluates to 0. @item -Wintrinsics-std @@ -1008,6 +1009,15 @@ it as @code{EXTERNAL} procedure because of this. @option{-fall-intrinsics} can be used to never trigger this behavior and always link to the intrinsic regardless of the selected standard. +@item -Wno-overwrite-recursive +@opindex @code{Woverwrite-recursive} +@cindex warnings, overwrite recursive +Do not warn when @option{-fno-automatic} is used with @option{-frecursive}. Recursion +will be broken if the relevant local variables do not have the attribute +@code{AUTOMATIC} explicitly declared. This option can be used to suppress the warning +when it is known that recursion is not broken. Useful for build environments that use +@option{-Werror}. + @item -Wreal-q-constant @opindex @code{Wreal-q-constant} @cindex warnings, @code{q} exponent-letter diff --git a/gcc/fortran/lang.opt b/gcc/fortran/lang.opt index b8bf7fe7508..1b296c92d19 100644 --- a/gcc/fortran/lang.opt +++ b/gcc/fortran/lang.opt @@ -293,6 +293,10 @@ Wopenmp-simd Fortran ; Documented in C +Woverwrite-recursive +Fortran Warning Var(warn_overwrite_recursive) Init(1) +Warn that -fno-automatic may break recursion. + Wpedantic Fortran ; Documented in common.opt diff --git a/gcc/fortran/options.c b/gcc/fortran/options.c index a0f95fa8832..47042a25eab 100644 --- a/gcc/fortran/options.c +++ b/gcc/fortran/options.c @@ -419,7 +419,8 @@ gfc_post_options (const char **pfilename) gfc_warning_now (0, "Flag %<-fno-automatic%> overwrites %<-fmax-stack-var-size=%d%>", flag_max_stack_var_size); else if (!flag_automatic && flag_recursive) - gfc_warning_now (0, "Flag %<-fno-automatic%> overwrites %<-frecursive%>"); + gfc_warning_now (OPT_Woverwrite_recursive, "Flag %<-fno-automatic%> " + "overwrites %<-frecursive%>"); else if (!flag_automatic && flag_openmp) gfc_warning_now (0, "Flag %<-fno-automatic%> overwrites %<-frecursive%> implied by " "%<-fopenmp%>"); diff --git a/gcc/testsuite/gfortran.dg/no_overwrite_recursive_1.f90 b/gcc/testsuite/gfortran.dg/no_overwrite_recursive_1.f90 new file mode 100644 index 00000000000..f12c4b8a4c7 --- /dev/null +++ b/gcc/testsuite/gfortran.dg/no_overwrite_recursive_1.f90 @@ -0,0 +1,11 @@ +! { dg-do compile } +! { dg-options "-fno-automatic -frecursive" } +! +! Test case contributed by Mark Eggleston +! + +program test + ! do nothing +end program + +! { dg-warning "Flag '-fno-automatic' overwrites '-frecursive'" "warning" { target *-*-* } 0 } diff --git a/gcc/testsuite/gfortran.dg/no_overwrite_recursive_2.f90 b/gcc/testsuite/gfortran.dg/no_overwrite_recursive_2.f90 new file mode 100644 index 00000000000..09445375481 --- /dev/null +++ b/gcc/testsuite/gfortran.dg/no_overwrite_recursive_2.f90 @@ -0,0 +1,10 @@ +! { dg-do compile } +! { dg-options "-fno-automatic -frecursive -Wno-overwrite-recursive" } +! +! Test case contributed by Mark Eggleston +! + +program test + ! do nothing +end program + -- 2.11.0