# HG changeset patch
# User Chris Cannam
# Date 1684496319 -3600
#      Fri May 19 12:38:39 2023 +0100
# Node ID 5303511e7b86027c419e5b8208c55ea8d3466558
# Parent  2041cbd43cf7ce011435feadb12f08c0ef8d4974
# Parent  8f14da435ced183afa560ecc8846a98bb6c678b0
Merge from branch libatomic-check

diff --git a/COMPILING.md b/COMPILING.md
--- a/COMPILING.md
+++ b/COMPILING.md
@@ -320,7 +320,7 @@
 Library        Build option               CPP define            Notes
 -------        ------------               ----------            -----
 
-Built-in       -Dfft=builtin              -DUSE_BQRESAMPLER     Default.
+Built-in       -Dresampler=builtin        -DUSE_BQRESAMPLER     Default.
                                                                 Intended to give high quality
                                                                 for time-varying pitch shifts
                                                                 in real-time mode.
diff --git a/meson.build b/meson.build
--- a/meson.build
+++ b/meson.build
@@ -131,6 +131,24 @@
                                args: '-lm')
 
 
+# Do we need libatomic?
+#
+libatomic_dep = dependency('', required : false)
+libatomic_test_program = '''
+#include <atomic>
+int main() {
+    std::atomic<int> i;
+    std::atomic<double> d;
+    return int(i.is_lock_free() && d.is_lock_free());
+}
+'''
+if cpp.compiles(libatomic_test_program, name : 'test program using std::atomic')
+  if (not cpp.links(libatomic_test_program, name : 'test program using std::atomic requires -latomic'))
+    libatomic_dep = cpp.find_library('atomic', required : true)
+  endif
+endif
+
+
 # Find out whether we can build the optional JNI target. Thanks to Eli
 # Schwartz for the fix here; this has been through a few previous
 # iterations. Initially we just looked for jni.h, but it's often in an
@@ -150,6 +168,11 @@
 have_jni = false
 have_java = add_languages('java', required: get_option('jni'))
 if have_java
+  # At the time of writing this causes a spurious Meson warning:
+  # "Project targets '>= 0.53.0' but uses feature introduced in
+  # '0.62.0': dep 'jni' custom lookup." It's spurious because this
+  # syntax worked before 0.62 as well, it just didn't invoke the
+  # custom lookup
   jni_dep = dependency('jni', required: false)
   have_jni = cpp.has_header('jni.h', dependencies: jni_dep, args: extra_include_args)
 endif
@@ -489,7 +512,7 @@
 
 general_include_dirs += get_option('extra_include_dirs')
 general_compile_args = [ arch_flags, feature_defines ]
-general_dependencies = [ feature_dependencies, thread_dep ]
+general_dependencies = [ feature_dependencies, thread_dep, libatomic_dep ]
 
 rubberband_additional_static_lib = ''
 
@@ -776,7 +799,7 @@
     dependencies: [
       rubberband_objlib_dep,
       general_dependencies,
-      sndfile_dep,
+      sndfile_dep
     ],
     install: true,
   )
diff --git a/src/finer/R3Stretcher.h b/src/finer/R3Stretcher.h
--- a/src/finer/R3Stretcher.h
+++ b/src/finer/R3Stretcher.h
@@ -42,6 +42,7 @@
 
 #include <map>
 #include <memory>
+#include <atomic>
 
 namespace RubberBand
 {