From b8df2c6ebd96f2cb06e19da909623085d7b23932 Mon Sep 17 00:00:00 2001
From: James McCoy <jamessan@jamessan.com>
Date: Sun, 7 Apr 2019 19:50:54 -0400
Subject: [PATCH 1/3] Make SHM_ALL to a variable instead of a compound literal
 #define

gcc-9 has [improved compliance] with the C spec for lifetime of compound
literals, tying their lifetime to block scope instead of function scope.
This makes the behavior comparable to all other automatic variables.

Using the SHM_ALL #define instantiated a compound literal local to an if
clause and assigned the address to a "char_u *".  Since the pointer was
then being used outside of the if clause, it was using an invalid
address.

[improved compliance]: https://gcc.gnu.org/gcc-9/porting_to.html#complit

Closes #9855
---
 src/nvim/option.c      | 9 +++++++++
 src/nvim/option_defs.h | 8 --------
 2 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/src/nvim/option.c b/src/nvim/option.c
index 348649036669c8..30dabcdd7df86c 100644
--- a/src/nvim/option.c
+++ b/src/nvim/option.c
@@ -310,6 +310,15 @@ static char *(p_scl_values[]) =       { "yes", "no", "auto", "auto:1", "auto:2",
   "yes:1", "yes:2", "yes:3", "yes:4", "yes:5", "yes:6", "yes:7", "yes:8",
   "yes:9", NULL };
 
+/// All possible flags for 'shm'.
+static char_u SHM_ALL[] = {
+  SHM_RO, SHM_MOD, SHM_FILE, SHM_LAST, SHM_TEXT, SHM_LINES, SHM_NEW, SHM_WRI,
+  SHM_ABBREVIATIONS, SHM_WRITE, SHM_TRUNC, SHM_TRUNCALL, SHM_OVER,
+  SHM_OVERALL, SHM_SEARCH, SHM_ATTENTION, SHM_INTRO, SHM_COMPLETIONMENU,
+  SHM_RECORDING, SHM_FILEINFO,
+  0,
+};
+
 #ifdef INCLUDE_GENERATED_DECLARATIONS
 # include "option.c.generated.h"
 #endif
diff --git a/src/nvim/option_defs.h b/src/nvim/option_defs.h
index c71ce9175b5f69..2075d2819cacc0 100644
--- a/src/nvim/option_defs.h
+++ b/src/nvim/option_defs.h
@@ -179,14 +179,6 @@ enum {
   SHM_RO, SHM_MOD, SHM_FILE, SHM_LAST, SHM_TEXT, SHM_LINES, SHM_NEW, SHM_WRI, \
   0, \
 })
-/// All possible flags for 'shm'.
-#define SHM_ALL ((char_u[]) { \
-  SHM_RO, SHM_MOD, SHM_FILE, SHM_LAST, SHM_TEXT, SHM_LINES, SHM_NEW, SHM_WRI, \
-  SHM_ABBREVIATIONS, SHM_WRITE, SHM_TRUNC, SHM_TRUNCALL, SHM_OVER, \
-  SHM_OVERALL, SHM_SEARCH, SHM_ATTENTION, SHM_INTRO, SHM_COMPLETIONMENU, \
-  SHM_RECORDING, SHM_FILEINFO, \
-  0, \
-})
 
 /* characters for p_go: */
 #define GO_ASEL         'a'             /* autoselect */

From 6572c995fb5a3b7dc41f077e0434810e6679f96d Mon Sep 17 00:00:00 2001
From: James McCoy <jamessan@jamessan.com>
Date: Sun, 7 Apr 2019 20:01:05 -0400
Subject: [PATCH 2/3] Remove MSVC optimization workaround for SHM_ALL

---
 src/nvim/option.c | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/src/nvim/option.c b/src/nvim/option.c
index 30dabcdd7df86c..026d8e21214b43 100644
--- a/src/nvim/option.c
+++ b/src/nvim/option.c
@@ -2495,11 +2495,6 @@ static bool valid_filetype(char_u *val)
   return true;
 }
 
-#ifdef _MSC_VER
-// MSVC optimizations are disabled for this function because it
-// incorrectly generates an empty string for SHM_ALL.
-#pragma optimize("", off)
-#endif
 /*
  * Handle string options that need some action to perform when changed.
  * Returns NULL for success, or an error message for an error.
@@ -3391,9 +3386,6 @@ did_set_string_option(
 
   return errmsg;
 }
-#ifdef _MSC_VER
-#pragma optimize("", on)
-#endif
 
 /*
  * Simple int comparison function for use with qsort()

From 61eff5d23826e423e29bc21de09e181921028c7c Mon Sep 17 00:00:00 2001
From: James McCoy <jamessan@jamessan.com>
Date: Mon, 8 Apr 2019 08:02:44 -0400
Subject: [PATCH 3/3] lint

---
 src/nvim/option.c | 17 ++++++-----------
 1 file changed, 6 insertions(+), 11 deletions(-)

diff --git a/src/nvim/option.c b/src/nvim/option.c
index 026d8e21214b43..bfb1de096da953 100644
--- a/src/nvim/option.c
+++ b/src/nvim/option.c
@@ -2495,10 +2495,8 @@ static bool valid_filetype(char_u *val)
   return true;
 }
 
-/*
- * Handle string options that need some action to perform when changed.
- * Returns NULL for success, or an error message for an error.
- */
+/// Handle string options that need some action to perform when changed.
+/// Returns NULL for success, or an error message for an error.
 static char_u *
 did_set_string_option(
     int opt_idx,                       // index in options[] table
@@ -3387,18 +3385,15 @@ did_set_string_option(
   return errmsg;
 }
 
-/*
- * Simple int comparison function for use with qsort()
- */
+/// Simple int comparison function for use with qsort()
 static int int_cmp(const void *a, const void *b)
 {
   return *(const int *)a - *(const int *)b;
 }
 
-/*
- * Handle setting 'colorcolumn' or 'textwidth' in window "wp".
- * Returns error message, NULL if it's OK.
- */
+/// Handle setting 'colorcolumn' or 'textwidth' in window "wp".
+///
+/// @return error message, NULL if it's OK.
 char_u *check_colorcolumn(win_T *wp)
 {
   char_u      *s;