From f18fae4c689a68bd50ce34d6b9c1f014c2f220a2 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <slouken@libsdl.org>
Date: Tue, 4 Oct 2022 16:46:29 -0700
Subject: [PATCH] Use DWARF 4 debug information when building using mingw

See this bug for more information:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101377

Fixes https://github.com/libsdl-org/SDL/issues/6139
---
 configure    | 36 ++++++++++++++++++++++++++++++++++++
 configure.ac | 21 +++++++++++++++++++++
 2 files changed, 57 insertions(+)

diff --git a/configure b/configure
index f626d12e4..c592ce213 100755
--- a/configure
+++ b/configure
@@ -22773,6 +22773,41 @@ printf "%s\n" "$have_clang_objc_arc" >&6; }
     fi
 }
 
+CheckGDwarf4()
+{
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for GCC -gdwarf-4 option" >&5
+printf %s "checking for GCC -gdwarf-4 option... " >&6; }
+    have_gcc_gdwarf4=no
+
+    save_CFLAGS="$CFLAGS"
+    CFLAGS="$save_CFLAGS -gdwarf-4"
+    cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+    int x = 0;
+
+int
+main (void)
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"
+then :
+  have_gcc_gdwarf4=yes
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $have_gcc_gdwarf4" >&5
+printf "%s\n" "$have_gcc_gdwarf4" >&6; }
+    CFLAGS="$save_CFLAGS"
+
+    if test x$have_gcc_gdwarf4 = xyes; then
+        EXTRA_CFLAGS="$EXTRA_CFLAGS -gdwarf-4"
+    fi
+}
+
 CheckVisibilityHidden()
 {
     { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for GCC -fvisibility=hidden option" >&5
@@ -28503,6 +28538,7 @@ printf "%s\n" "#define SDL_TIMER_UNIX 1" >>confdefs.h
         if test x$enable_loadso = xyes; then
             have_loadso=yes
         fi
+        CheckGDwarf4
         CheckDeclarationAfterStatement
         CheckDummyVideo
         CheckOffscreenVideo
diff --git a/configure.ac b/configure.ac
index 4a4023e19..b75a9e12f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1515,6 +1515,26 @@ CheckObjectiveCARC()
     fi
 }
 
+dnl See if GCC's -gdwarf-4 is supported
+dnl See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101377 for why this is needed on Windows
+CheckGDwarf4()
+{
+    AC_MSG_CHECKING(for GCC -gdwarf-4 option)
+    have_gcc_gdwarf4=no
+
+    save_CFLAGS="$CFLAGS"
+    CFLAGS="$save_CFLAGS -gdwarf-4"
+    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
+    int x = 0;
+    ]],[])], [have_gcc_gdwarf4=yes],[])
+    AC_MSG_RESULT($have_gcc_gdwarf4)
+    CFLAGS="$save_CFLAGS"
+
+    if test x$have_gcc_gdwarf4 = xyes; then
+        EXTRA_CFLAGS="$EXTRA_CFLAGS -gdwarf-4"
+    fi
+}
+
 dnl See if GCC's -fvisibility=hidden is supported (gcc4 and later, usually).
 dnl  Details of this flag are here: http://gcc.gnu.org/wiki/Visibility
 CheckVisibilityHidden()
@@ -3969,6 +3989,7 @@ case "$host" in
         if test x$enable_loadso = xyes; then
             have_loadso=yes
         fi
+        CheckGDwarf4
         CheckDeclarationAfterStatement
         CheckDummyVideo
         CheckOffscreenVideo