[nasm:nasm-2.15.xx] configure.ac: add option to compile with suggestion warnings

[nasm-bot for H. Peter Anvin (Intel)]

Commit-ID:  50200cc0d3d9847d40c5ed3ff87c47c1bde5d6dc
Gitweb:     http://repo.or.cz/w/nasm.git?a=commitdiff;h=50200cc0d3d9847d40c5ed3ff87c47c1bde5d6dc
Author:     H. Peter Anvin (Intel) <hpa at zytor.com>
AuthorDate: Thu, 30 Jul 2020 17:37:42 -0700
Committer:  H. Peter Anvin (Intel) <hpa at zytor.com>
CommitDate: Thu, 30 Jul 2020 17:37:42 -0700

configure.ac: add option to compile with suggestion warnings

Add a configure option to enable suggestion warnings, currently a set
of -Wsuggest-attribute=* warnings.

Signed-off-by: H. Peter Anvin (Intel) <hpa at zytor.com>


---
 configure.ac | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/configure.ac b/configure.ac
index 7b727693..17132af9 100644
--- a/configure.ac
+++ b/configure.ac
@@ -396,6 +396,18 @@ PA_ARG_ENABLED([werror],
   PA_ADD_CFLAGS([-Werror=vla])]
 )
 
+dnl Warnings that are probabilistic based on the compiler version, and
+dnl only should be used specifically when looking for opportunities to
+dnl address or optimize these cases.
+PA_ARG_ENABLED([suggestions],
+ [compile with compiler suggestion warnings enabled],
+ [PA_ADD_CFLAGS([-Wsuggest-attribute=pure])
+  PA_ADD_CFLAGS([-Wsuggest-attribute=const])
+  PA_ADD_CFLAGS([-Wsuggest-attribute=noreturn])
+  PA_ADD_CFLAGS([-Wsuggest-attribute=format])
+  PA_ADD_CFLAGS([-Wsuggest-attribute=cold])
+  PA_ADD_CFLAGS([-Wsuggest-attribute=malloc])])
+
 dnl
 dnl Test compiler features. On some compilers, this can be affected
 dnl by -Werror options, so run this *after* those options are added.