fix build on arm32 without neon

from: https://github.com/tesseract-ocr/tesseract/pull/4154

diff --git a/neon-detect.patch b/neon-detect.patch
new file mode 100644 (file)
index 0000000..0eeec7c
--- /dev/null
+++ b/neon-detect.patch
@@ -0,0 +1,49 @@
+From b1e48789d61d995740762f66f505385db42410a5 Mon Sep 17 00:00:00 2001
+From: Jan Palus <jpalus@fastmail.com>
+Date: Mon, 30 Oct 2023 01:36:57 +0100
+Subject: [PATCH] Check if NEON extension are actually available
+
+User may pass own compiler flags to configure which override those
+provided by project through automake. Therefore it is possible for user
+on ARM platform to pass CXXFLAGS=-mfpu=vfp which will effectively
+disable NEON even though used compiler supports -mfpu=neon (since user
+supplied flags take precedence compiler invocation will use flags:
+-mfpu=neon -mfpu=vfp). Instead of checking whether compiler supports
+-mfpu=neon flag, check if NEON extensions are available by checking if
+__ARM_NEON is defined when compiling with -mfpu=neon and user supplied
+flags combined.
+
+Signed-off-by: Jan Palus <jpalus@fastmail.com>
+---
+ configure.ac | 18 ++++++++++++++----
+ 1 file changed, 14 insertions(+), 4 deletions(-)
+
+diff --git a/configure.ac b/configure.ac
+index 0b38537229..0514b619c5 100644
+--- a/configure.ac
++++ b/configure.ac
+@@ -178,10 +178,20 @@ case "${host_cpu}" in
+     ;;
+ 
+   arm*)
+-
+-    AX_CHECK_COMPILE_FLAG([-mfpu=neon], [neon=true], [neon=false], [$WERROR])
+-    AM_CONDITIONAL([HAVE_NEON], $neon)
+-    if $neon; then
++    SAVE_CXXFLAGS="$CXXFLAGS"
++    CXXFLAGS="-mfpu=neon $CXXFLAGS"
++    AC_MSG_CHECKING([for NEON support])
++    AC_COMPILE_IFELSE(
++    [AC_LANG_PROGRAM([], [[
++    #ifndef __ARM_NEON
++           #error
++    #endif
++    ]])],
++    [neon=yes], [neon=no])
++    AC_MSG_RESULT([$neon])
++    CXXFLAGS="$SAVE_CXXFLAGS"
++    AM_CONDITIONAL([HAVE_NEON], test "xyes" = "x$neon")
++    if test "xyes" = "$neon"; then
+       AC_DEFINE([HAVE_NEON], [1], [Enable NEON instructions])
+       NEON_CXXFLAGS="-mfpu=neon"
+       AC_SUBST([NEON_CXXFLAGS])

diff --git a/tesseract.spec b/tesseract.spec
index bab92e357b4c54da5149941e7a2016e74e6365ba..3b5381bebbd6cb83f4134764cc97ad92bb8ff127 100644 (file)
--- a/tesseract.spec
+++ b/tesseract.spec
@@ -16,6 +16,7 @@ Group:                Applications/Graphics
 #Source0Download: https://github.com/tesseract-ocr/tesseract/releases
 Source0:       https://github.com/tesseract-ocr/tesseract/archive/%{version}/%{name}-%{version}.tar.gz
 # Source0-md5: 53de961804ccbcb83b73122f721d8f83
+Patch0:                neon-detect.patch
 URL:           https://github.com/tesseract-ocr/
 %{?with_opencl:BuildRequires:  OpenCL-devel}
 BuildRequires: asciidoc
@@ -92,6 +93,7 @@ Statyczne biblioteki Tesseracta.
 
 %prep
 %setup -q
+%patch0 -p1
 
 %build
 %{__libtoolize}