From 433e0523561c83f2c2f586a9534e5e12a2e06abb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Attila=20Ol=C3=A1h?= <atl@google.com>
Date: Thu, 24 Sep 2020 16:22:25 +0000
Subject: [PATCH 1/2] Set the --shared-memory linker flag for Emscripten
 builds.

This is only needed when building with WEBP support, which uses atomics,
therefore the linker needs the --shared-memory flag. The flag cannot be
added globally because not all executables link against libwebp.
---
 contrib/addtiffo/CMakeLists.txt |  6 ++++++
 contrib/dbs/CMakeLists.txt      | 11 +++++++++++
 test/CMakeLists.txt             | 15 +++++++++++++++
 tools/CMakeLists.txt            | 27 +++++++++++++++++++++++++++
 4 files changed, 59 insertions(+)

diff --git a/contrib/addtiffo/CMakeLists.txt b/contrib/addtiffo/CMakeLists.txt
index b7482635..45e733cd 100644
--- a/contrib/addtiffo/CMakeLists.txt
+++ b/contrib/addtiffo/CMakeLists.txt
@@ -32,3 +32,9 @@ include_directories(${PROJECT_SOURCE_DIR}/libtiff
 
 add_executable(addtiffo addtiffo.c tif_overview.c tif_ovrcache.c tif_ovrcache.h)
 target_link_libraries(addtiffo tiff port)
+
+if(WEBP_SUPPORT AND EMSCRIPTEN)
+  # Emscripten is pretty finnicky about linker flags.
+  # It needs --shared-memory if and only if atomics or bulk-memory is used.
+  target_link_options(addtiffo PUBLIC "-Wl,--shared-memory")
+endif()
diff --git a/contrib/dbs/CMakeLists.txt b/contrib/dbs/CMakeLists.txt
index b2e809b2..ff3ce20c 100644
--- a/contrib/dbs/CMakeLists.txt
+++ b/contrib/dbs/CMakeLists.txt
@@ -41,3 +41,14 @@ target_link_libraries(tiff-rgb tiff port)
 add_subdirectory(xtiff)
 
 extra_dist(README)
+
+if(WEBP_SUPPORT AND EMSCRIPTEN)
+  # Emscripten is pretty finnicky about linker flags.
+  # It needs --shared-memory if and only if atomics or bulk-memory is used.
+  foreach(target tiff-bi
+                 tiff-grayscale
+                 tiff-palette
+                 tiff-rgb)
+    target_link_options(${target} PUBLIC "-Wl,--shared-memory")
+  endforeach()
+endif()
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index ff91f78b..e5d92dfe 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -220,6 +220,21 @@ target_link_libraries(defer_strile_writing tiff port)
 add_executable(testtypes testtypes.c)
 target_link_libraries(testtypes tiff port)
 
+if(WEBP_SUPPORT AND EMSCRIPTEN)
+  # Emscripten is pretty finnicky about linker flags.
+  # It needs --shared-memory if and only if atomics or bulk-memory is used.
+  foreach(target ascii_tag
+                 custom_dir
+                 defer_strile_loading
+                 defer_strile_writing
+                 long_tag
+                 rewrite
+                 short_tag
+                 strip_rw)
+    target_link_options(${target} PUBLIC "-Wl,--shared-memory")
+  endforeach()
+endif()
+
 set(TEST_OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/output")
 file(MAKE_DIRECTORY "${TEST_OUTPUT}")
 
diff --git a/tools/CMakeLists.txt b/tools/CMakeLists.txt
index 886d4549..ff2a1ddc 100644
--- a/tools/CMakeLists.txt
+++ b/tools/CMakeLists.txt
@@ -123,3 +123,30 @@ if(HAVE_OPENGL)
   install(TARGETS tiffgt
           RUNTIME DESTINATION "${CMAKE_INSTALL_FULL_BINDIR}")
 endif()
+
+if(WEBP_SUPPORT AND EMSCRIPTEN)
+  # Emscripten is pretty finnicky about linker flags.
+  # It needs --shared-memory if and only if atomics or bulk-memory is used.
+  foreach(target fax2ps
+                 fax2tiff
+                 pal2rgb
+                 ppm2tiff
+                 raw2tiff
+                 rgb2ycbcr
+                 thumbnail
+                 tiff2bw
+                 tiff2pdf
+                 tiff2ps
+                 tiff2rgba
+                 tiffcmp
+                 tiffcp
+                 tiffcrop
+                 tiffdither
+                 tiffdump
+                 tiffinfo
+                 tiffmedian
+                 tiffset
+                 tiffsplit)
+    target_link_options(${target} PUBLIC "-Wl,--shared-memory")
+  endforeach()
+endif()

From 2b9abce31bd445c66e8a311daf05a92e17b24df4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Attila=20Ol=C3=A1h?= <atl@google.com>
Date: Thu, 24 Sep 2020 17:24:12 +0000
Subject: [PATCH 2/2] Also pass --shared-memory to raw_decode.

This is needed when building for Emscripten with *both* WEBP and JPEG
support.
---
 test/CMakeLists.txt | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index e5d92dfe..5a1a7420 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -233,6 +233,9 @@ if(WEBP_SUPPORT AND EMSCRIPTEN)
                  strip_rw)
     target_link_options(${target} PUBLIC "-Wl,--shared-memory")
   endforeach()
+  if(JPEG_SUPPORT)
+    target_link_options(raw_decode PUBLIC "-Wl,--shared-memory")
+  endif()
 endif()
 
 set(TEST_OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/output")